rrs discovery cruise dy081, july 6 – august 8th 2017 st john’s, … · 2020-01-09 · shipboard...
TRANSCRIPT
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DY081CRUISEREPORT
RRSDiscoveryCruiseDY081,July6th–August8th2017
StJohn’s,Canada–Southampton,UK
ICY-LAB
IsotopeCYclingintheLABradorSea
CruiseReport
KatharineR.Hendry,UniversityofBristol
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CONTENTS
TableofContents
CONTENTS....................................................................................................................................2
Chapter1:Personnelonboard.....................................................................................................4Allcrew..................................................................................................................................................4Sciencepartywatchlist..........................................................................................................................5
Chapter2:Rationale,aimsandobjectives....................................................................................6Thesamplingobjectivesofthecruise......................................................................................................6
Chapter3:Cruiseoverview...........................................................................................................8Timeline.................................................................................................................................................8Cruisenarrative....................................................................................................................................10Stationlist............................................................................................................................................14
Chapter4:Sitesummariesandmaps..........................................................................................17OrphanKnoll........................................................................................................................................17Nuuk.....................................................................................................................................................21SouthernGreenland.............................................................................................................................21
Chapter5:Technicalreport........................................................................................................26Acousticsoperations.............................................................................................................................26Coringoperations.................................................................................................................................38CTDoperations.....................................................................................................................................40Glideroperations..................................................................................................................................43RemotelyOperatedVehicleoperations................................................................................................46SAPsoperations....................................................................................................................................56Towfishoperations...............................................................................................................................57
Chapter6:Physicaloceanography..............................................................................................58Introduction.........................................................................................................................................58Summaryofsensordeploymentsandpreliminaryresults.....................................................................58Summaryofgliderdeployments...........................................................................................................69
Chapter7:Watersampling.........................................................................................................70Introduction.........................................................................................................................................70Summaryofwatersamplingevents......................................................................................................70SummaryofICY-LABprojectseawaterparameters...............................................................................74Samplingprotocolsforcomplementarystudies....................................................................................77Porefluidsamplingandcoreincubations...............................................................................................83Shipboardwateranalyses.....................................................................................................................86
Chapter8:StandAlonePumps...................................................................................................89Introduction.........................................................................................................................................89SummaryofSAPSevents......................................................................................................................89Samplingprotocol.................................................................................................................................89
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Chapter9:Sedimentsampling....................................................................................................91Introduction.........................................................................................................................................91SampleCollection.................................................................................................................................91SedimentRecovery...............................................................................................................................93ShipboardAnalyses..............................................................................................................................96
Chapter10:Biologicalsampling.................................................................................................101Introduction.......................................................................................................................................101Corals.................................................................................................................................................102Sponges..............................................................................................................................................103
Chapter11:Scleractiniancorals.................................................................................................106SamplingProtocol...............................................................................................................................106SamplingLocations.............................................................................................................................106
Chapter13:Microplasticssampling...........................................................................................108Introduction.......................................................................................................................................108Summaryofsamples...........................................................................................................................108SampleProcessing..............................................................................................................................108
References................................................................................................................................110
ManythankstotheMasterandcrewoftheRRSDiscoveryforalltheirassistanceduringthismission.
ICY-LABisfundedbytheEuropeanResearchCouncil.
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Chapter1:PersonnelonboardAllcrew1 COX JOANNALOUISE Master2 MAHON ANDREW C/O3 LEGGETT COLINJAMES 2/O4 WILLIAMS THOMASJAY 3/O5 WOODLAND HAZELELIZABETH Doctor6 BILLS JAMES C/E7 KEMP CHRISTOPHERMARTIN 2/E8 EVANS DANIELCHRISTOPHER 3/E9 QUITHER MARTIN 3/E10 BRAZIER THOMASPHILIP ETO11 BULLIMORE GRAHAM PCO12 MACDONALD JOHN CPOS13 COOK STUARTCLIVE CPOD14 GREGORY NATHANIELJAMES POD15 CRABB GARY SG1A16 WILLCOX SIMONPAUL SG1A17 PEPPIN CHRISTOPHER SG1A18 DWYER ANDREW SG1A19 BROOMHALL NATHAN ERPO20 LYNCH PETERANTHONY H/Chef21 LINK WALTERJOHNTHOMAS Chef22 CARAHILLO CLEMENTINAMARIA Stwd23 WILLIAMS DENZIL A/Stwd24 ANNETT AMBERLUELLA Scientist25 BADGER MARCUS Scientist26 BATES STEPHANIELAUREN Scientist27 COOPER ADAMJOHN Scientist28 CUSHMAN GRACEGARCIA Scientist29 GOODWIN CLAIREELOISE Scientist30 HENDRY KATHARINE PI31 HOY SHANNONKELSEY Scientist32 HUVENNE VEERLEANNIDA Scientist33 JACOBEL ALLISONWOOD Scientist34 NG HONGCHIN Scientist35 OPHER JACOBGEORGE Scientist36 PICKERING REBECCAANN Scientist37 ROBINSON LAURAFRANCES Scientist38 ROWLAND GEORGEHENRY Scientist39 SAMPERIZVIZCANINO ANA Scientist40 TAYLOR MICHELLELISA Scientist41 WILLIAMS JAMES Scientist42 TURNER DAVIDRUSSELL Tech43 MOUNTIFIELD DOUGAL Tech44 CAMERON CANDICEANNE Tech45 EDGE DAVID Tech46 DAVIES ALLAN Tech47 LOCKE RUSSELLANDREW Tech48 WEBB ANDREWTHOMAS Tech49 RICHARDS ELLALOUISE Tech50 LEADBEATER ANDREWJOHN Tech51 VIERARIVERO JOSUEDANIEL Tech52 BRIDGER MARTINJOHN SST
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Sciencepartywatchlist
8am–8pm
DrKatharineHendry(UniversityofBristol)
4am–4pm
WatchLeader:DrVeerleHuvenne(NationalOceanographyCentre,Southampton)DrAmberAnnett(UniversityofSouthampton)DrMarcusBadger(TheOpenUniversity)GraceCushman(ColumbiaUniversity,US)DrClaireGoodwin(HuntsmanMarineScienceCentre)DrAllisonJacobel(ColumbiaUniversity,US)JacobOpher(BritishAntarcticSurvey)RebeccaPickering(DauphinLaboratory,UniversityofAlabama,US)*AnaSamperiz(UniversityofBristol)*watchrescheduledonsomedaysforincubationexperiments
4pm-4am
WatchLeader:ProfLauraRobinson(UniversityofBristol)ShannonHoy(UniversityofNewHampshire,US)DrHongChinNg(UniversityofBristol)DrMichelleTaylor(OxfordUniversity)GeorgeRowland(UniversityofBristol)AdamCooper(UniversityofSouthampton)JamesWilliams(CardiffUniversity)DrStephanieBates(UniversityofBristol)
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Chapter2:Rationale,aimsandobjectives
Thehigh-latituderegionsareexperiencingsomeofthemostrapidchangesobservedinrecentdecades.Arctictemperaturesarerisingtwiceasfastastheglobalmean,Greenland’sglaciersareexperiencingsignificantmassloss,multi-yearArcticsea-iceisdeclining,andtheNordicSeasarewarmingatanacceleratedrate.Theseprocessesareimportantlocally,buttheireffectsarelikelytohaveaglobalimpact:forexample,theNorthAtlanticreceivesfreshwaterfromtheArctic,GreenlandandCanadaandisaformationlocusofthedeep-watermasses,whichrepresentamajorcomponentofoceancirculationthatdrivesglobalheatandnutrientfluxes.
Concurrentlytotherecentlyobservedchangesinicedynamicsandaccessibility,therehasbeenasignificantincreaseincommercialinterestofthenaturalresourcesintheecosystemsoftheArctic,surroundingseasandhigh-latitudeNorthAtlantic.Anunderstandinghownaturalresources-includingfisheries,birdandmammalstocksthatareessentialforfoodandtourism–willrespondinthefuturetoincreasinganthropogenicstressonaregionalandglobalscalereliesonanunderstandingofmarinebiogeochemistryandthesourcesandsinksofessentialnutrients.
TheoverallaimofICY-LABistounderstandnutrientandisotopecyclingintheclimaticallycriticalbutunderstudiedregionsoftheLabradorSeaandGreenlandfjords,andtheimpactofcryosphere,biosphereandhydrosphereonthebiogeochemistryoftheregionandtheglobaloceans.TheapproachofICY-LABwillbetocapturethewholebiogeochemicalsysteminareasofmarkedenvironmentalchangeusingcarefulfieldsamplingstrategies,withresearchexpeditionstocoastalGreenlandandtheopenoceanLabradorSea.DY081representsthekeyoceaniccomponentofthissamplingcampaign,focusingontheinfluenceofmeltwateronnutrientcyclingintheLabradorSea,usingthesiliconcycleasamodelsystem.Siliconisakeynutrientfordiatoms,algaethatareresponsibleforalargeproportionofcarbonuptakeinmarinesystems.
ThesamplingobjectivesofthecruiseObjectivestobecarriedoutbyDrKateHendryandDrHong-ChinNg,withprojectpartnersnamedinparentheses.
1) Mappingofsamplingareas(DrVeerleHuvenne)
2) Detectionandsamplingoffreshwaterinputfromglaciatedenvironmentsa. Physicaloceanography(JacobOpher;DrKateHendryandresearchgroup)b. Watercolumnacoustics(ShannonHoy)c. Geochemicaltracersoffreshwater(DrKateHendryandresearchgroup)d. Nutrientandnutrientisotopesampling(KateHendryandresearchgroup;alsosamplingforDr
SianHenley(UniversityofEdinburgh))
3) Investigationofinteractionsatthesediment-waterinterface(DrKateHendryandresearchgroup)a. Megacoreandpushcoresamplingb. Porefluidsamplingc. Coreincubationexperiments
4) Investigationofbiogeographyofsiliceousorganismsa. Chlorophyllsampling(KateHendryandresearchgroup)b. Silicon-32uptakeexperiments(RebeccaPickering,ProfJeffreyKrause(DauphinLab))
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c. Spongesamplingfortaxonomyandbiogeography(ClaireGoodwin)
5) Complementarystudiesandprojectsa. Tracemetalsandtracemetalisotopes(DrAmberAnnett,andsamplingforDrSusanLittle,Prof
TinaVanderFlierdt(ImperialCollege,London),andDrKevinBurton(DurhamUniversity))b. Benthicbiologyandgenetics(DrMichelleTaylor,andsamplingforDrJoanaXavier)c. Phytophysiology(samplingforDrRupertPerkins(CardiffUniversity))d. Organicgeochemistry(DrMarcusBadger)e. Habitatmapping(DrVeerleHuvenne)f. Palaeoclimate(ProfLauraRobinsonandGeorgeRowland;DrAllisonJacobelandsamplingfor
ProfJerryMcManus(ColumbiaUniversity);JamesWilliams)g. Microplasticsresearch(ProfLauraRobinson,withDrLucyWoodall)
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Chapter3:CruiseoverviewTimelineTABLE1:TIMELINEOFCRUISEEVENTSANDLOCATIONS.
Date Location ActivityJuly6th Transit July7th Transit OrphanKnoll CTDoperationsCTD01,SAP01;MultibeamsurveyJuly8th OrphanKnoll Multibeamsurvey;CoringMGA01+GVY01;ROVdive
327(start)July9th OrphanKnoll ROVdive327(end);DeployTowfishFSH01;SurveyJuly10th OrphanKnoll RetrieveTowfish;ROVdive328(aborted);ROVdive
329(start)July11th OrphanKnoll ROVdive329(end);CoringMGA02+GVY02;ROV
dive330(start)July12th OrphanKnoll ROVdive330;CTD02;ROVdive331(start)
July13th Transit OrphanKnoll ROVdive331(end);DeployTowfish;Multibeamsurvey;StarttransittoGreenland;SADCPturnedon.
July14th Transit
July15th Transit
July16th Transit
July17th Transit Nuuk GLD01;GLD02;SAPStest;MGA03;StartofCTDgrid
July18th Nuuk CTDgridcontinues.Badweatherhaltsoverthesidescience.
July19th Nuuk Sciencecontinuesasweatherimproves.CTDgridcontinues.
July20th Nuuk ROVdive332(aborted)followedbyROVdive333.
July21st Nuuk ROVdive334;transittosouthernline;SAPS.
July22nd Nuuk ROVdive335.
July23rd Nuuk Multibeamsurvey;ROVdive336.CTD15.
July24th Transit Nuuk CTD16,andSAPSatsamelocation.Recoveredgliderssuccessfully;MGA04.
July25th Transit
July26th Transit SWGreenland CTD17.Towfishrecovered.ROV337(aborted),towfishdeployed,CTD18.
July27th SWGreenland CTD19,SAP05,MGA05,ROV338(start).
July28th SWGreenland ROV338,MGA06.
July29th SWGreenland ROV339,Towfishin,CTD20.
July30th SWGreenland CTD21,CTD22.
July31st Transit SWGreenland CTD23,CTD24,SAP06,MGA07,GVY03,GVY04,GVY05.
August1st–8th Transit
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FIGURE1:OVERVIEWMAPOFDY081SHIPROUTE.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF55˚N.
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Cruisenarrative
Timesareshiptime,unlessstated.
Sunday2ndJuly2017:MostofthesciencepartyarriveinStJohn’s,Canada.
Monday3rdJuly2017:RemainderofsciencepartyarriveinStJohn’s,Canada.
Tuesday4thJuly2017:Safetybriefingforscienceparty1100.Briefingwithcaptain1300;informedbycaptainthatsailingduetobedelayedapprox.24hoursduetocrewchange.
Wednesday5thJuly2017:Radionuclidesafetybriefing1030.ROVwalkthrough1300.Databaseplanningmeeting1600.
Thursday6thJuly2017:Shipsails0800(shiptimechangedtoGMT-2).CTDwalkthrough1400.Musterandlifeboatdrill1600.Introductorysciencetalk1700.
Friday7thJuly2017:ShiparrivesatOrphanKnoll.STN001CTDdownto3800mat1600withbottlesfiredat12depths(timeondeck2036GMT).STN002SAPSat2400and200metreswaterdepth(twoSAPSateachdepth,withGFFandSuporfilters)(timeondeck0212GMT).OneSAPSflooded,andtwobatteryfailurespartwaythroughpumpingbutmaterialcollectedonallfilters.CTDcableapparentlydamagedpost-SAPS,butsuccessfullyfixed.MultibeamsurveyofOrphanSeamount.
Saturday8thJuly2017: SurveycompleteandcoresitelocatedtonorthwestofOrphanSeamount.STN003Megacoreat3700mmetresdepth,with8successfulcores(timeondeck1024GMT).STN004gravitycoreinsamelocation,successful,with5m15cmcollectedfrom3700m(timeondeck1346GMT).Corecatchercollected,andcoresectionedinto1.5metrelengths.
Sunday9thJuly2017:RecoveryofSTN005ROV327in3600mwaterdepthonOrphanSeamount,southernside;successfulcollectionofspongesandcorals;12xsedimentcores;6xNiskin(1failure).STN006towfishdeployedovernight,withthreesamplingevents(deployed1815GMT;recovered0720GMT).ItwasnotedthattheTowfishneededtobepulledinbeforefinalisingtheROVpositionforadive.
Monday10thJuly2017:DeploymentofSTN007ROV328in1700mwaterdepth.Collectionofcupcorals,blackcoral,sponges,andophioroidsforgenetics;pushcoresandNiskins.Horizontalthrustergroundfaultledtoaborteddive(timeondeck1632GMT).Alsosomeproblemswiththesuctiondevice.Groundfaultproblemsnotdiagnosedatsurface,butallsystemsappearedtobeoperatingfully.RedeployedSTN008ROV239.Collectionofliveandfossilsolitarycorals,andarmouredholothurians;pushcoresandNiskins.
Tuesday11thJuly2017: ROV239ondeck1737GMT.STN009MegacoreMGA02deployed1900GMTinwaterdepthof1770m;fourtubessuccessfulsampledforporefluids,coreincubationexperimentandsections.STN010gravitycoreGVY02deployed2035GMT,with4.5msedimentsrecovered.DeploymentofSTN011ROV330at2315GMT,collectionoffossilandlivecorals,spongeswithcrinoids,andcollectionofimagesforphotogrammetry.
Wednesday12thJuly2017:ROV330continued,recoveredat1214GMT.STN012CTD02deployedin1800mwaterdepth,with24bottlesfiredat8depths(recovered1453GMT).DeploymentofSTN013ROV331at1609GMT,collectionoffossilcorals,livingcorals,spongesandotherbiology,pushcores.TheKraftarmleakedoil,sotherewasaslightlyearlyrecovery.
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Thursday13thJuly2017:ROV331continued,butanoilproblemrelatingtoanarmmeantthatthecrewretrievedtheROVapproximatelyanhourearlyat0630GMT.TowfishinwaterforSTN014.MultibeamsurveytonorthofROV328-331,beforecommencingtransittoGreenland.ShipboardADCPturnedon,andMultibeamsurveycarriedoutontransit.Towfishsamplescollectedatintervals.Duetoweather,decisionwastakentovisitSWGreenlandsitefirst.
Friday14thJuly2017:Transitcontinued.
Saturday15thJuly2017:Transitcontinued.Weatherforecastimproved,sodecisionmadetogotoNuuksitefirstasoriginallyplanned.
Sunday16thJuly2017: Transitcontinued.
Monday17thJuly2017:TransittoNuuksite.ArrivetosouthofNuuksite,deployedSTN015GLD01(Coprolite)offstarboardsideinwaterat0611GMTanddivingby0650;STN016GLD02(HSB)inwaterat0755GMT.Connectivityissuesresultedinminorfilecorruption,whichwasresolvedbeforethegliderdivedat0910GMT.STN017CTD03wasdeployedat0949GMTnearbytocalibratethegliders(approx.2000mwaterdepth),andtoprovideaSVPfortheMultibeamacoustics.Watersampleswereonlytakenforsilicon32experimentsandradiummeasurements.TransitandMultibeamsurveytoNuuksite,stoppingbeforeCTDgridforSAPstest(inwater1810GMTandbackondeck2040);previouslyfloodedcasingwasshowntobewatertightat1000mfor1hour.STN018MGA03deployedandrecoveredat2212GMT,with8fulltubes.Afterashorttransit,the“GloriousGrid”startedwithSTN019CTD04deployed.Highfluorescencelayerwasshallowerinthewatercolumnonthewayup,withotherevidencefordynamicsurfacelayers.
Tuesday18thJuly2017: STN020SAP02;oneSAPonlypumped8L,theothersworkedwell.Didn’tmanagetogetthebottomSAPsdownfullytodepthduetoslowdeploymentofwire,sosampledatapproximately650ratherthan900m.CTDgridcontinuedwithSTN21CTD05(Niskin7leaked),STN22CTD06(Niskins9and18didn’tfire),andSTN23CTD07(7leakedand18didn’tfire)onthefirstline.Weatherpreventedcontinuingworkontheshelf;transitandMultibeambathymetrysurveyduringbadweather.
Wednesday19thJuly2017:Over-the-sidesciencecontinuesafterweatherimproved.STN24CTD08(potentiallymovedduetocurrent)andSTN25CTD09onthirdline(notethattherewasacautiousapproachtothebottomduetosteeptopography).PauseforwindtodiedownbeforemovingontoSTN26CTD10(Niskins5and7didn’tfireorleaked)andSTN27CTD11(withnewNiskin7)ontheshelf,followedbySTN28CTD12(noLADCP)andSTN29CTD13offtheshelf.TowfishrecoveredatendoflastCTD.
Thursday20thJuly2017: STN030ROVdive332wasdeployedbutrecoveredduetoagroundfaultondeployment.ProblemrectifiedandSTN031ROVdive333wasdeployedwithsameaimsandobjectivesas332.Collectionofsponges,corals,bivalves,fossilcoralsandsedimentcoreswithNiskinsfired.ROVdiverecoveredat2305GMT.STN32Towfishinwaterat2323GMT.
Friday21stJuly2017:FinalCTDofthe“GloriousGrid”STN33CTD14;furtherCTDsshorewardswerenotconsideredduetotimeandwaterdepthconstraints,andconsiderationofwaterprofile.STN34ROVdive334resonandphotogrammetrydivebackonwallfoundduringROV333,recovered1605GMT;alsocollectedpushcores(onebroken)forporefluidsandanothernetoffossilcorals.STN35SAP03recovered2340GMT;Minniefailed(onlypumped14L)butotherSAPSsuccessfulwithapproximately600LpumpedthroughbothSupors.
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Saturday22ndJuly2017: TransitfurthersouthforSTN36ROVdive335;collectionofliveandfossilcorals,sponges,sediments(withporefluidsampling).Attheendofthedive,thecurrentswereverystrongandtherewerenogoodsedimentstosample.
Sunday23rdJuly2017: RecoverROV335at0337GMT.TransitandMultibeamsurveytoprepareforSTN37ROV336;collectionofsponges,corals,phototransit(interruptedbyoctopus),sediments(withporefluidsampling).TowfishSTN38FSH04at2105GMT.ContinuethirdgridlinefurtherintoglacialtroughwithSTN39CTD15,attemptingtosamplelowersalinitylayers(Niskin9leaked).
Monday24thJuly2017:ContinuedthirdgridlineintotroughwithSTN40CTD16;STN41SAPSatsamelocationwithlastunitondeckat0714GMT,withthreesuccessfulfilters.TransitandMultibeamtositeofgliderrecovery.SuccessfulrecoveryofCoproliteat1313GMT(endofSTN15);successfulrecoveryofHSBat1425GMTdespitethefogrollingin(endofSTN16).Transitsouth,viaman-over-boarddrillandMegacoreatSTN42MGA04witheightsuccessfulcores.BegintransittoSWGreenlandsite.Multibeamsurveyonroute.
Tuesday25thJuly2017: TransittoSWGreenlandsite.Multibeamcontinues.
Wednesday26thJuly2017:ArrivalatSWGreenlandsite.STN43CTD17instrongcurrents;bottle9leakedagain.Otherwise,asuccessfulcast.MultibeamsurveyforROVsite.Towfishrecovered.STN44ROV337wasdeployed,butwasabortedduetostrongcurrents.TowfishredeployedatSTN45.TransittoSTN46CTD18intrough.Notedsurfacesalinitydroppedconsiderably.
Thursday27thJuly2017: ContinuetoworkatsamelocationwithSTN47CTD19,sampledforDrAmberAnnettonly(notepossiblejellyfishfoulingcouldhaveimpactedbackscatter),andSTN48SAP05,withfoursuccessfulpumps.Lookforsedimentcoringsiteonthetroughsite,resultinginSTN49MGA05with8successfulcores,andoneNiskin(filtered).FurtherMultibeamtolocatepossiblenewROVsite;alsokeepinganeyeontheADCPforcurrentstrength.Sitelocated,withsurfacecurrentslessthanpreviously,droppingatdepth.STN50ROV338deployed;initiallydivedtoseafloortochecklandinginthecurrents(allwasfinewithdeploymentanddiving)andtotakepushcores,beforeheadingtoplanneddivestart.
Friday28thJuly2017:ContinuedROV338,managingtomakeacoursedespitechallengingconditionsofstrongsurfacecurrentsandicebergs.Collectedsponges,fossilcoralframework,andDesmophyllumsolitarycoral.Haddifficultyfindingfurthergoodsedimentpushcoresatdepth;ondeck1814GMT.STN51MGA06,with8successfulcores,andoneNiskin(filtered);recovered2217GMT.Multibeamsurveyfornewdivesite.
Saturday29thJuly2017: ContinueMultibeamsurvey,findingnewsiteforSTN52ROV339.Startofdiveatdeepestpoint,withsandybottom,rocks,sponges,solitarycorals,holothuriansandaray.Divehadto‘bluewater’toavoidicebergactivity;restartedagaintocompletedive,recoveredat2151GMT.TowfishinforSTN53FSH06.ShortsteamtonearbyopenwaterforSTN54CTD20,1200m.AllNiskinsnowworkingafterpreviousbottlechangeandmaintenance.
Sunday30thJuly2017: CTD20recoveredat0018GMT.TransitandMultibeamtoCapeFarewell.Arrivalatstation,withslightdelaytoallowtheROVtobewinchedtomid-aftdeckfordemob.FollowedpromptlybySTN55CTD21.AllNiskinsworked.TransitedfurtherintolandtoattemptaCTD,butwasrepositionedduetosea-iceconditions.STN56CTD22ascloseaspossibletosea-iceedge(allNiskinsworked),thenretreatfurtherforadditionalpotentialCTDsite.Decidedtosearchforcoringsite,andcarriedoutSTN57MGA07;alleightcores,butshortlengths.
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Monday31stJuly2017:Furtherretreatfromsea-iceforSTN58CTD23(forDrAnnettonly)andSTN59CTD24.FollowedatthesamelocationsbySTN60SAP06;allworkedexceptdeeperGFFfilter,Chloe.ShorttransittoErikDrift.STN61GVY03at1660m,4.8m,butwithvoidsodecidedtotryagain.STN62GVY04camebackwithonly82cm,butdecidedtocarryontodeeperwaters.STN63GVY05.Increasingwindsbroughtforwardtheendofover-the-sidescience.MultibeamandshipboardADCPcontinuedduringtransitbacktoUK.
Saturday5thAugust2017: MultibeamandshipboardADCPturnedoffonentryintoIrishEEZat1202GMT.
Tuesday8thAugust2017: DockingatNationalOceanographyCentre,EmpressDock,Southampton.
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StationlistTABLE2:STATIONLISTFORCRUISEDY081.CTD=CONDUCTIVITYTEMPERATUREDEPTHAND24-NISKINROSETTE;SAP=STANDALONEPUMPS;MGA=MEGACORE;GVY=GRAVITYCORE;ROV=REMOTELYOPERATEDVEHICLE;FSH=TOWFISH;GLD=GLIDER.
Site Station Gear JdayStart StartTime
(GMT)
StartLat
(DD)
StartLon
(DD)
Start
Depth(m)
JdayEnd EndLat
(DD)
EndLon
(DD)
EndDepth
(m)
OrphanKnoll 1 CTD001 188 17:25:00 50.17428 -45.43948 3813.0 188 50.1743 -45.4395 3814.0OrphanKnoll 2 SAP001 188 22:03:00 50.17430 -45.43948 3815.0 189 50.1743 -45.4395 3814.0OrphanKnoll 3 MGA001 189 07:57:00 50.15915 -45.50830 3721.0 189 50.1592 -45.5083 3721.0OrphanKnoll 4 GVY001 189 11:24:00 50.15919 -45.50835 3721.0 189 50.1592 -45.5083 3721.0OrphanKnoll 5 ROV327 189 16:19:00 50.04158 -45.37940 3550.8 190 50.0832 -45.3594 1941.0OrphanKnoll 6 FSH001 190 18:10:00 50.08318 -45.35940 1932.0 191 50.5528 -46.1944 1677.0OrphanKnoll 7 ROV328 191 07:50:00 50.55481 -46.19323 1669.2 191 50.5564 -46.1956 1576.7OrphanKnoll 8 ROV329 191 20:48:00 50.55182 -46.19227 1792.0 192 50.5698 -46.1836 1527.0OrphanKnoll 9 MGA002 192 19:02:00 50.51547 -46.27902 1769.8 192 50.5155 -46.2790 1770.0OrphanKnoll 10 GVY002 192 20:35:00 50.51546 -46.27900 1770.0 192 50.5155 -46.2790 1770.0OrphanKnoll 11 ROV330 192 23:23:00 50.55118 -46.19071 1825.5 193 50.5512 -46.1934 1717.0OrphanKnoll 12 CTD002 193 13:11:00 50.54236 -46.17057 1850.0 193 1846.0OrphanKnoll 13 ROV331 193 16:15:00 50.50629 -46.08250 1848.0 194 1586.0OrphanKnoll 14 FSH002 194 07:11:40 50.50770 -46.08840 1837.1 200 50.5755 -45.9865 1594.0Nuuk 15 GLD001 198 06:11:00 62.90416 -52.62882 2357.0 205 63.7147 -53.0865 1313.0Nuuk 16 GLD002 198 07:55:00 62.92231 -52.65246 2333.0 205 62.9269 -52.6561 620.0Nuuk 17 CTD003 198 09:49:00 62.92231 -52.65246 2123.0 198 2064.0Nuuk 18 MGA003 198 21:14:00 63.81541 -53.77431 1301.0 198 63.8154 -53.7743 1301.0Nuuk 19 CTD004 198 23:22:00 63.85162 -53.79918 1084.0 199 63.8516 -53.7992 1084.0Nuuk 20 SAP002 199 02:42:00 63.85227 -53.79763 1080.0 199 63.8530 -53.7981 1080.0Nuuk 21 CTD005 199 07:14:00 63.87635 -53.56517 966.0 199 63.8822 -53.5674 972.0Nuuk 22 CTD006 199 10:17:00 63.90095 -53.36405 659.0 199 63.9010 -53.3641 657.0Nuuk 23 CTD007 199 12:56:00 63.91773 -53.13293 103.0 199 63.9177 -53.1329 103
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Nuuk 24 CTD008 200 01:11:00 63.41803 -53.14670 1681.0 200 63.4286 -53.1528 1711Nuuk 25 CTD009 200 05:22:00 63.45380 -52.87985 915.0 200 63.4538 -52.8799 922Nuuk 26 CTD010 200 09:43:00 63.49629 -52.61218 339.0 200 63.4963 -52.6122 338Nuuk 27 CTD011 200 14:55:00 63.72713 -52.83125 69.6 200 63.7271 -52.8313 70.2Nuuk 28 CTD012 200 17:44:00 63.69635 -53.08266 653.3 200 63.6963 -53.0827 653Nuuk 29 CTD013 200 20:28:00 63.66162 -53.33311 1550.0 200 63.6616 -53.3331 1549Nuuk 30 ROV332 201 02:45:00 63.86858 -53.28953 964.0 201 63.8704 -53.2901 950Nuuk 31 ROV333 201 03:49:00 63.86612 -53.28869 970.0 201 63.8657 -53.2834 805Nuuk 32 FSH003 201 23:23:00 63.86599 -53.28424 822.8 202 63.9535 -52.9167 67Nuuk 33 CTD014 202 02:24:00 63.95358 -52.91682 66.5 202 63.9536 -52.9168 66.7Nuuk 34 ROV334 202 07:00:00 63.86511 -53.28258 807.0 202 63.8651 -53.2784 683Nuuk 35 SAP003 202 20:36:00 63.59505 -52.95646 786.0 202 63.5950 -52.9565 784.8Nuuk 36 ROV335 203 03:38:00 63.33217 -52.77710 1281.00 204 63.3317 -52.7550 898Nuuk 37 ROV336 204 10:51:00 63.60375 -52.91897 515.0 204 63.6112 -52.9032 345.9Nuuk 38 FSH004 204 21:05:00 63.61123 -52.90324 351.2 207 60.0941 -47.3158 1056Nuuk 39 CTD015 204 23:54:00 63.51954 -52.35627 446.4 205 63.5195 -52.3563 445.6Nuuk 40 CTD016 205 02:29:00 63.57532 -52.14668 487.3 205 63.5753 -52.1467 486.6Nuuk 41 SAP004 205 04:41:00 63.57537 -52.14660 486.0 205 63.5754 -52.1463 488Nuuk 42 MGA004 205 20:23:00 63.55297 -52.22512 518.8 205 63.5530 -52.2291 519S.Greenland 43 CTD017 207 05:10:00 59.84621 -47.24472 2780.0 207 59.8517 -47.2485 2782S.Greenland 44 ROV337 207 17:33:00 60.09451 -47.31853 1037.2 207 60.1063 -47.4009 1048S.Greenland 45 FSH005 207 20:30:00 60.11090 -47.41771 1050.00 208 60.0898 -46.6496 1111.4S.Greenland 46 CTD018 207 23:37:00 60.24523 -46.88678 536.0 208 60.2452 -46.8868 536S.Greenland 47 CTD019 208 02:46:00 60.23971 -46.85244 501.0 208 60.2391 -46.8544 503S.Greenland 48 SAP005 208 05:30:00 60.24474 -46.88747 534.0 208 60.2447 -46.8875 534S.Greenland 49 MGA005 208 10:53:00 60.26180 -46.89084 522.3 208 60.2618 -46.8908 572S.Greenland 50 ROV338 208 18:46:00 60.09000 -46.62533 603.50 209 60.0862 -46.6497 1064S.Greenland 51 MGA006 209 21:20:00 60.11595 -46.66351 1326.0 209 60.1160 -46.6635 1327
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DY081CRUISEREPORT
S.Greenland 52 ROV339 210 07:04:00 59.94672 -46.54810 1148.0 210 59.9423 -46.5069 589S.Greenland 53 FSH006 210 22:07:00 59.94239 -46.50713 596.0 212 59.9395 -43.7783 1907S.Greenland 54 CTD020 210 23:00:00 59.90837 -46.49170 1270.6 211 59.9084 -46.4917 1270S.Greenland 55 CTD021 211 12:56:00 59.21163 -44.58042 2030.4 211 59.2162 -44.6061 2036S.Greenland 56 CTD022 211 18:16:00 59.48646 -44.36462 884.7 211 59.4865 -44.3646 884S.Greenland 57 MGA007 211 21:21:00 59.45644 -44.41508 1291.0 211 59.4565 28.1216 1292S.Greenland 58 CTD023 211 23:37:00 59.39499 -44.49790 1521.0 212 59.3950 24.4314 1522S.Greenland 59 CTD024 212 01:33:00 59.39502 -44.49837 1522.0 212 59.3951 24.4419 1522S.Greenland 60 SAP006 212 03:44:00 59.39518 -44.49851 1522.0 212 59.3953 24.4501 1521S.Greenland 61 GVY003 212 11:14:00 58.99701 -43.58429 1670.0 212 58.9967 60.5188 1669S.Greenland 62 GVY004 212 13:11:00 58.94073 -43.59906 1608.0 212 58.9397 57.0991 1608S.Greenland 63 GVY005 212 17:49:00 58.60611 -43.77831 1907.0 212 58.6061 37.0833 1907
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DY081CRUISEREPORT
Chapter4:Sitesummariesandmaps
OrphanKnoll
OrphanKnollsitewasselectedasadistalcomparisonsitefortheICY-LABproject,andforcomplementarypalaeoclimate,biologicalandhabitatmappingstudies.Thesitewasdividedintosouthernandnorthernregions.
FIGURE2:MAPOFORPHANKNOLLWITHSHIPTRACK.PRODUCEDINMERCATORPROJECTIONWITHASTANDARD
PARALLELOF50˚N.
FIGURE3:MAPOFSOUTHERNORPHANKNOLLWITHSTATIONLOCATIONS.PRODUCEDINMERCATORPROJECTIONWITHA
STANDARDPARALLELOF50˚N.
FIGURE4:MAPOFNORTHERNORPHANKNOLLWITHSTATIONLOCATIONS.PRODUCEDINMERCATORPROJECTIONWITHA
STANDARDPARALLELOF50˚N.
18
DY081CRUISEREPORT
Figure2
19
DY081CRUISEREPORT
Figure3
20
DY081CRUISEREPORT
Figure4
21
DY081CRUISEREPORT
Nuuk
TheNuuksitewasselectedthemainstudylocationfortheICY-LABproject,andincludedaCTDgridandgliderdeploymentforhigh-resolutionwatercolumnstudiessurroundingglacialtroughs,inadditiontotheothermethodologiesemployedthroughoutthecruise.
FIGURE5:MAPOFNUUKSITEWITHCRUISETRACKANDSTATIONS(OVERTHEPAGE).PRODUCEDINMERCATOR
PROJECTIONWITHASTANDARDPARALLELOF63˚N.
SouthernGreenland
TheSouthernGreenlandsitewasselectedforprovidingglacialtroughsthatcouldactasdirectcomparisonstotheNuuksitefortheICY-LABproject.Thesiteisstronglyinfluencedbybothicebergsandsea-ice.ThesiteisdividedintotworegionstermedNarsaqandCapeFarewell.
FIGURE6:MAPOFSOUTHERNGREENLANDSITEWITHCRUISETRACK(OVERTHEPAGE).PRODUCEDINMERCATOR
PROJECTIONWITHASTANDARDPARALLELOF63˚N.
FIGURE7:MAPOFSOUTHERNGREENLANDSITE(NARSAQ)WITHSTATIONS.PRODUCEDINMERCATORPROJECTIONWITH
ASTANDARDPARALLELOF63˚N.
FIGURE8:MAPOFSOUTHERNGREENLANDSITE(CAPEFAREWELLANDERIKDRIFT)WITHSTATIONS.PRODUCEDIN
MERCATORPROJECTIONWITHASTANDARDPARALLELOF63˚N.
22
DY081CRUISEREPORT
Figure5
52°0'W52°30'W53°0'W53°30'W54°0'W
64°0
'N
64°0
'N
63°3
0'N
63°3
0'N
63°0
'N
63°0
'N
0 20 40Nautical Miles
0 30 60Kilometers
NUUK, GREENLAND
Ship TrackBathymetry
50°W55°W
65°N
64°N
63°N
62°N
100 m900 m1400 m2200 m
Projection: World Mercator, Standard Parallel = 63 Degrees North
CTDFSHGLDGVYMGAROVSAP
CTD014
CTD005
MGA003
CTD004
CTD007
FSH002ROV334ROV332
ROV333
CTD006
SAP002
CTD013CTD012
CTD011
CTD008CTD009
CTD010
ROV335
SAP004
CTD015
MGA004
CTD002GLD001
GLD002
ROV336
SAP003
FSH004
CTD016
23
DY081CRUISEREPORT
Figure6
24
DY081CRUISEREPORT
Figure7
25
DY081CRUISEREPORT
Figure8
26
DY081CRUISEREPORT
Chapter5:Technicalreport
Acousticsoperations
DuringDY081,sixacousticsystemswererunfromtheship,andonefromtheROV:
- EM122multibeamechosounder(12kHz)- EM710multibeamechosounder- SBP120sub-bottomechosounder(2.5–6.5kHz)- EK60fishfindingechosounder(18,38,70,120,200,333kHz)- TeledyneOS075ADCP(75kHz)- TeledyneOS150ADCP(150kHz)- Reson7125multibeamechosounder(400kHz)
TheshipacousticsystemswerecoordinatedviatheK-Syncsystem(Figure9),toavoidinterferenceandcrosstalk.Forthemajorityofoperations,theEM122,SBP120,EK60,andtheOS150weresyncedtopingconcurrently,withtheEM122setasthemasterexternaltrigger.TheOS75wasoffsetfromthemaintriggergroupandtheEM710wassettofreeping.
FIGURE9:K-SYNCSET-UPFOROPERATIONSWITHALLSYSTEMSRUNNING.
Basicmanuallogswerekeptduringtheoperations,andhavebeenscannedaspdfdocuments.Summariesoftheseareprovidedinthetablesbelow.
27
DY081CRUISEREPORT
EM122MultibeamEchosounderTheEM122multibeamechosounderwasthemainmappingsystemusedthroughoutthecruise.Themapswereusedtoinformfurthersampling,andspecificallytodesigntheROVdives.EM122datawerecollectedcontinuouslyduringtransits,inadditiontothespecificsurveysthatwerecarriedoutateachofthestudyareas.Table4summarisesthebasicparametersforeachofthesectionsofdata.Intotal,55,868squarekilometresweremappedwiththeEM122.Thetablebelowsummarisesthebasicparametersforeachofthesectionsofdata.
TABLE3:RECORDINGTIMES,SVPANDLINENUMBERSFOREM122DATAFOREACHOFTHESTUDYAREAS.
Acquisitionsettings:Vesselspeed:specificsurveyswerecarriedoutat8kn,otherwisedatawerecollectedatthespeedthatwasmostappropriateforthevessel(e.g.10-11knduringtransit);
Swathangle:60deg,exceptincaseswhenoverlapwasnotsufficient,e.g.whenthecoursehadtobealteredbecauseofice;
Dataformat:datawerestoredasKongsberg.allfiles,with.wcdfilesforthewatercolumninformation;Navigation:GPSdatafromthePOS-MVsystem(theusualSeaPathGPShadproblemsatthestartofthecruise,hencethePOS-MVwasusedforthedurationoftheexpedition);
FurthersettingsinformationisprovidedintheFigure10.
28
DY081CRUISEREPORT
FIGURE10:SETTINGSFOREM122ECHOSOUNDER.
SoundvelocityinformationwastakenfromthevariousCTDcastscarriedoutthroughoutthecruise,whichwereappliedtothedataassoonastheywereavailable(seeTable3forinformationonwhichSVPwasusedinwhicharea).Inaddition,thesoundvelocityatthetransducerwasalsoused.Itwasnotedthat,duetoworkinginshallowconditionsclosetoriverandmeltwaterinputs,thesoundvelocityatthetransducerwasoftensignificantlydifferentfromthesurfacewatersoundvelocityintheSVPprofiles(redalarmonSIS).
DataProcessing:ThedatatypesrecordedfromtheEM122systemincludebathymetry,backscatterandwatercolumndata.Bathymetrydatawereprocessedon-boardwiththeCarisHIPS&SIPSsoftwarev.8,usingstandardsettingsandprocedures(dataimport,navigationandattitudecheck,applicationofa“zerotide”,griddingintoa25mx25mpixelBASEsurface).Eachbathymetrygrid,aswellasaninterpolatedsurface,wasexportedtoanASCIIgrid,aGeoTiff,aswellasaFledermausSDobject.ThevesselfileDisco_EM122_POS_MV.hvfwasusedforprocessing,withthefollowingoffsets:
TimeCorr:0.00X(m):-0.005Y(m):35.219Z(m):7.438Pitch(deg):0.00Roll(deg):0.00Yaw(deg):0.00
Whilepostprocessingon-board,someerrorswereapparentinthebathymetricgrids.Thesecouldbeeitherduetotherapidlychangingwatermasses,ortosomesystematicoffset.Furtherprocessingisrequiredtodetermineandfixtheseerrors.
29
DY081CRUISEREPORT
ThefinalbathymetrygridsarelistedinTable4andpresentedinFigure11.BackscatterdatawereprocessedusingthedefaultsettingsinFledermausFMGTandexportedasGeoTiff.Watercolumndatawerecollected,butexceptforoccasionalqualitycontrol,werenotprocessedfurtheron-board.
TABLE4:FINALEM122GRIDS.
Location FileName LinesContained
Projection Resolution(m) Area(km2)
TRS1 DY081_EM122_TRS_1a_25m 0000-0015 WGS84UTM22N
25 108
TRS1 DY081_EM122_TRS_1b_25m 0016-0038 WGS84UTM22N
25 1083
TRS1 DY081_EM122_TRS_1c_25m 0039-0055 WGS84UTM23N
25 1962
OrphanKnoll
DY081_EM122_OK_25m 0056-0147 WGS84UTM23N
25 3414
TRS2 DY081_EM122_TRS_2a_25m 0147-0170 WGS84UTM23N
25 2558
TRS2 DY081_EM122_TRS_2b_25m 0168-0195 WGS84UTM23N
25 2716
TRS2 DY081_EM122_TRS_2c_25m 0194-0221 WGS84UTM23N
25 2816
TRS2 DY081_EM122_TRS_2d_25m 0220-0244 WGS84UTM22N
25 3183
TRS2 DY081_EM122_TRS_2e_25m 0242-0285 WGS84UTM22N
25 4354
TRS2 DY081_EM122_TRS_2f_25m 0284-0317 WGS84UTM22N
25 3230
Nuuk DY081_EM122_Nuuk_25m 0318-0479 WGS84UTM22N
25 2538
TRS3 DY081_EM122_TRS_3a_25m 0478-0509 WGS84UTM22N
25 2406
TRS3 DY081_EM122_TRS_3b_25m 0508-0531 WGS84UTM22N
25 1981
Narsaq DY081_EM122_Narsaq_25m 0530-0637 WGS84UTM23N
25 1295
TRS4 DY081_EM122_TRS_4_25m 0636-0653 WGS84UTM23N
25 429
CapeFarewell
DY081_EM122_CapeFarewell_25m
0653-0688 WGS84UTM23N
25 1088
TRS5 DY081_EM122_TRS_5d_25m 0829-0874 WGS84UTM27N
25 4711
TRS5 DY081_EM122_TRS_5e_25m 0871-0904 WGS84UTM28N
25 3780
TOTALAREA= 55868
30
DY081CRUISEREPORT
FIGURE11:OVERVIEWOFTHEBATHYMETRICGRIDSOBTAINEDINTHEMAINSTUDYAREAS.
EM710MultibeamEchosounderTheEM710systemwasusedinitiallyforseabedmappingonthefirsttransitintheshallowwatersoffshoreStJohn’s.However,lateroninthecruisethissystemwassetupspecificallyforwatercolumnsurveyingdownto250mwd,whichmeantthatnofurtherseafloormapswerecreatedwiththissystem.AnoverviewofthebasicparametersandlinenumbersforeachofthecruisesectionsisprovidedinTable5.
TABLE5:RECORDINGTIMES,SVPANDLINENUMBERSFOREM710DATAFOREACHOFTHESTUDYAREAS.
Settings:Vesselspeed:specificsurveyswerecarriedoutat8kn,otherwisedatawerecollectedatthespeedthatwasmostappropriateforthevessel(e.g.10-11knduringtransit);
Swathangle:60deg,exceptincaseswhenoverlapwasnotsufficient,e.g.whenthecoursehadtobealteredbecauseofice;
Dataformat:datawerestoredasKongsberg.allfiles,with.wcdfilesforthewatercolumninformation.
Tocollecthighresolutiondataoftheupper250metersofthewatercolumn,thefollowingmethods(assuggestedbyJohnHughesClarke)werefollowed:
• SonarMode(RuntimeParameters>FilterandGains>SonarMode)• PingModesettoShallow• DepthSettings(min=0meters,max=250m)• EM710freepinging(unsyncedfromtheEM122)
Furthersettingsinformationisprovidedinthefigurebelow.
31
DY081CRUISEREPORT
FIGURE12:SETTINGSFOREM710ECHOSOUNDER.
Dataprocessing:DataprocessingfortheEM710wassimilartotheEM122:usingCarisHips&Sipsv.8forbathymetry(Table5),FledermausFMGTforbackscatter,andnofurthersystematicon-boardprocessingforthewatercolumndata.EquallytotheEM122,thePOS-MVbasedDiscoveryEM710vesselfilewasusedforthebathymetryprocessing(Disco_EM710_POS_MV.hvf).
Offsetswere:
TimeCorr:0.00X(m):-2.051Y(m):36.819Z(m):7.427Pitch(deg):0.00Roll(deg):0.00Yaw(deg):0.00
AnexampleofthewatercolumndataisprovidedinFigure13.
32
DY081CRUISEREPORT
FIGURE13:EXAMPLEIMAGEOFTHEEM710WATERCOLUMNSIGNAL,PLOTTINGPINGNUMBER(HORIZONTALAXIS)
AGAINSTDEPTH(VERTICALAXIS,0-250M).COLOURINTENSITYINDICATESBACKSCATTERSTRENGTH.THEDEEP
SCATTERINGLAYERCANBEIDENTIFIEDINTHEUPPERWATERCOLUMN.
SBP120Sub-BottomProfilerProfilesoftheseabedandsub-seabedwereobtainedwiththeKongsbergSBP120sub-bottomprofiler.Thisisachirpsystemwithvaryingfrequency,whichsharesthereceivertransducerswiththeEM122multibeamechosounder.Thesystemwasswitchedonforeverytransit,duringmultibeamsurveysandwhentheshipmovedbetweenstations.Itwasusedspecificallyhelpdeterminesuitablecoringsites.AnoverviewofthebasicparametersandrecordingtimesfortheSBP120isprovidedinTable6.
TABLE6:RECORDINGTIMES,SVPANDLINENUMBERSFORSBP120DATAFOREACHOFTHESTUDYAREAS.
Acquisitionsettings:Dataformat:SBP120dataweresavedbothasrawsegyfiles(.raw)andas‘processed’data(.seg),i.e.convolutedwiththesourcesweep,usingadateandtime-stampasfilename.Duringoperations,screenshotswerealsosavedasidentificationofsuitablecoringsitesetc.
FurthersettingsweremainlybasedonthedefaultconfigurationavailableontheRRSDiscovery,andarepresentedinFigure14.
33
DY081CRUISEREPORT
FIGURE14:SETTINGSFORSUB-BOTTOMPROFILER.
Dataprocessing:BasicdataprocessingandvisualisationfortheSBP120profileswascarriedoutusingtheLinuxfreeware‘SeismicUnix’software.Asimplecommandlinewasusedtoreadinthe.segfiles,addinthetimedelaysandplottheprofilesinpost-scriptformat.AnexampleoftheresultisshowninFigure15.
Segyreadtape=/cdrive/Data/SBP120/seg/20170718221312.segendian=0|segyclean|sushifttmin=1.2tmax=2.2|supsimageperc=98>/cdrive/Data/SBP120/ps/20170718221312.ps
FIGURE15:EXAMPLESBP120PROFILEFROMTRANSIT2,DISPLAYINGTWO-WAYTRAVELTIMEAGAINSTSHOTPOINT
NUMBER.
34
DY081CRUISEREPORT
EK60fish-findingechosounderTheKongsbergEK60systemwasusedtoimagethewatercolumn,morespecificallytoimagethedeepscatteringlayerandthepotentialcontactsbetweenwatermasses(showninFigure16).ItwasonlyswitchedonatthestartoftheworkaroundNuuk.Datawererecordedbothduringtransitsandwhilestationaryate.g.CTDstations.AnoverviewoftherecordingtimesforeachoftheresearchareasduringthecruiseisgiveninTable7.
TABLE7:RECORDINGTIMESFOREK60DATAFOREACHOFTHESTUDYAREAS.
FIGURE16:EK60DISPLAYSHOWINGDIURNALMIGRATIONATTHENUUKSITE.
Acquisitionsettings:TheEK60wassetupasperinstructionsbyKevinJerram,CenterforCoastalandOceanMapping,asshowninFigure17.
35
DY081CRUISEREPORT
FIGURE17:ACQUISITIONSETTINGSUSEDFORTHEDIFFERENTFREQUENCIESOFTHEEK60SYSTEM.
ThreedaysafterswitchingontheEK60,itwasdiscoveredthattheEK60hadpreviouslynotbeenreceivingnavigationinformation.Thiswascausedbyanincorrectpositiontalkeridusedduringsetup(INvsGP).Tocorrectthis,thefollowingmethodwasemployed:
INSTALL>NAVIGATION
POSITIONTALKERID=GP
Nodataprocessingwasperformedon-boardfortheEK60.
TeledyneAcousticDopplerCurrentProfilersTheOceanSurveyor(OS)instrumentsareVesselMountedAcousticDopplerCurrentProfilers(VMADP)manufacturedbyTeledyneRDinstruments.TheyaresecuredonadropkeelinsurfacewatersnearthecentreandbeneaththeRRSDiscovery.TheVMADPsmeasurethehorizontalcurrentvelocityprofile.TheparameterswereheldconstantforthedurationofOSmeasurements(13thJuly–5thAugust),andthetrackingmodewasalternated.Bottomtrackingmodewassuitableforperiodsspentontheshelfwhenthewaterwassufficientlyshallowandwatertrackingmodewasselectedindeeperwatersandonthecontinentalslope.Thecollectionofbottomtrackingdataisnecessaryfortheinstrumentcalibrations,notcarriedoutonboardthiscruise.Inrealitysuccessforthebottomtrackingmodewasonlyachievedinregionswherethebottomdepthwasnomorethan200mforthe150kHzdevice.Bottomtrackingdatawereonlycollectedforthe150kHzinstrumentclosetoNuukintermittentlybetween18thJuly–24thJuly.
Real-timedatawasperiodicallyacquiredfromtheVMADCPs.Asitcamein,thesedataweredisplayedthroughtheVmDassoftware(version1.48)onamonitorforeachADCP.Standardloggingcheckswereestablishedtoensurethatthecurrentprofilerswerecontinuingtocollectdata.Logsheetswerefilledouttoconfirmthattheensemblenumberwasincrementingandthatthedatafilesintheoutputdirectorywereincreasinginsize.AnotherimportantthingtomonitorwasthedriftoftheinternalclockofthecomputerrunningtheVmDassoftwarefromtheshipsGPSclock.Therewerenoproblemswiththedataacquisitiontoreport.Tolimitthesizeoftheoutputdatafilesandassistfutureprocessing,theVMADCPswereresetandthusnewfilesinitiated.Fileswereresetusuallydailybutoccasionallyranwithoutresettingforaslongas3days.RawdatafileswereautomaticallystoredintheAcousticsfolderofthecruisenetworkdrive.
36
DY081CRUISEREPORT
TABLE8:CONFIGURATIONSFORSHIP-MOUNTEDADCPS.
TeledyneOS075ADCPConfigurations:Narrowband,singlepingprofilemode16mdepthbins8mblankingdistance3secondsbetweenensembles1200mmaximumsearchingdepth
TeledyneOS150ADCPConfigurations:Narrowband,singlepingprofilemode8mdepthbins4mblankingdistance2secondsbetweenensembles800mmaximumsearchingdepth
Reson7125multibeamechosounderOneROVswathdivewascompletedduringthecruise(Dive334),andtheset-upchosenwasforforwardmappingasdevelopedundertheCODEMAPprogramme(Huvenneetal.,2011;Robertetal.,2017).ThismeantthattheSCORPIOcamerawastakenoffthevehicletomakespacefortheReson7125tobemountedonthefront.TheportbioboxandNiskinbottles(seetechnicalreportfortheROVoperations)weretakenoff,inordertoaccommodatetheelectronicsbottleoftheResonsystem.ThesetupisillustratedinFigure18.
FIGURE18:RESON7125TRANSDUCERSETUPONROVISIS.
ThesystemsettingsforthissurveyarelistedinTable9,andtheoffsetsofthevarioussensorsversusthecommonreferencepointonISISarelistedinthetablebelow.Inaddition,insidethe7Skacquisitionsoftware,thehardwareconfigurationoffsetsbetweenRxandTxweresetasfollowX=-0.125m,Y=-0.125mandZ=0.031mwithheadtilt=0°.Rollstabilisationwasswitchedoff,asithasbeennotedbeforethatthisgiveserrorsduringthesurvey.
Thevehiclewasflowninasetofparallelpasses,eachpassbeingcarriedoutataconstantdepthandwithanapproximatelyconstantdistancefromthecliffface(seetablesbelow).Surveyswerecarriedoutwithanominalheadingof135°forthefirstsectionofthecliff,and214°forthesecondsection.Datawererecordedat40-50m(depthsof755mand775m)and20-25m(depthsof740m,765mand790m)distancefromthewall.
37
DY081CRUISEREPORT
TABLE9:RESONSURVEYSETTINGSFORDIVE334
MBESFrequency 400kHz
Distancewall 40m 20m
Depth 755m 775m 740 765 790
Beamangle 120-140°
Power 203-207dB
Gain 40dB
Absorption 90dB/km
Spreading 30dB/km
Duration (atseabed)
4h40min
Surveyspeed 0.2-0.3kn
Maxpulserate 10p/s
Pulselength 40µs
TABLE10:OFFSETSFORTHEVARIOUSSENSORSVERSUSACOMMONREFERENCEPOINTONISIS(FRONTOFVEHICLE)AS
USEDFORTHEFORWARDMAPPINGAPPROACH,WITHINTHECONVENTIONALVEHICLEREFERENCEFRAME(X:POSITIVE
STARBOARD,Y:POSITIVEFORWARD,Z:POSITIVEUP,ALLINMETRES).
X Y Z
Compatt(USBL) 1.46 -1.01 0.36
Doppler -0.17 -0.58 2.19
MBES 0.34 -0.22 -0.12
Octans(attitude) -0.49 0.00 0.86
Parascientific(depth) 0.00 -0.55 1.48
38
DY081CRUISEREPORT
Coringoperations
IdentificationofcoringsitesSeabedsurveyingwasperformedpriortocoringoperationsateachlocationusingaKongsbergSub-BottomProfiler(SBP-120)andaKongsbergMultibeamEchosounder(EM-122).Samplingsiteswereselectedinareasofflatbathymetry,characterizedbythicklayersofsedimentdisplayingfeaturesconsistentwithquasi-linearsedimentation(e.g.identifiablestratigraphiclayers).Anexampleofasub-bottomprofileacquiredfromNuukformegacoreMGA04canbeseeninthefigurebelow.
FIGURE19:EXAMPLEOFSBPPROFILEFROMNUUK.
MegacoreSedimentswerecollectedusingtheNMFmegacorer(Figure20),toobtainshortcoresandundisturbedsediment-waterinterfacematerialforbiogeochemicalresearch.Themegacorerwasdeployedandrecoveredoffthestarboardsideonthetrawlwinch.Eighttubeswereusedforeachdeployment:fourwithoutholesandfourwithholesdrilledforporefluidsampling(tapedupwithducttapefordeployment).Onceondeckallcorebarrelswereremovedfromtherigandpluggedwithrubberbungs.Coresweresecuredinarefrigeratedroomusingawoodenrackandremainedinthislocationuntilsubsamplingcommenced.Sedimentsub-sampleswerestoredineithertherefrigeratedroomorina-20°Cfreezerdependingontheanalysesplanned.
Inadditiontosediments,themegacorerwasequippedwitha10LNiskinbottletocollectbottom-watersamples.TheNiskinbottledwasriggedtofireonimpactwiththeseafloor.
39
DY081CRUISEREPORT
FIGURE20:RECOVERYOFMEGACOREMGA04ONJULY24TH.ALLEIGHTCORESCONTAINEDSEDIMENTANDTHE
SEDIMENT-WATERINTERFACE:HALFOFTHETUBESWEREDRILLEDFORPOREFLUIDSAMPLING,ANDTAPEDUPFOR
DEPLOYMENT.PHOTOBYM.BADGER.
GravitycoreSedimentswerecollectedusinga6mlongbarrelgravitycore(Figure21)loweredtotheseafloor,deployedfromthestarboardsideonthetrawlwinch,loweredinitiallyat40m/minbeforeslowingto10-15m/minat100mabovetheseafloor.Thecorerwassunkintosedimentswiththeaidofa1-ton(approximate)weightontopofthebarrel.Duetothelimitationsofthetrawlwinch,thebarrellengthwaslimitedto6manddeploymentto4000m.
FIGURE21:GRAVITYCORERECOVERY.PHOTOBYA.JACOBEL.
PushcoresTheROVwasequippedwith6-12tubesforthecollectionofsmallcores.TheKraftarmwasusedtopickupeachcoreusingaT-handleinsertedatthetopofeachcylinder,andpushitintothesediment.Threeorfourreplicatecoreswerecollectedateachsamplingsite.Sometubesweredrilledwithholesforthecollectionofporefluids(tapedupduringdeployment).SeeROVtechnicaldetailsforfurtherinformation.
40
DY081CRUISEREPORT
CTDoperations
AllCTDcastswereundertakenwiththestainlesssteelCTDframeandused10LNiskinwatersamplers(Figure22).Sea-Bird35TemperatureandSea-Bird3Ptemperaturesensorswereinstalledonthe9Plusunderwaterunit.AcableconnectedtheSea-Bird35toboththe9PlusandtheSea-Bird32carousel.HousedonthevaneweretheSea-Bird43OxygenandthesecondarySea-Bird3Ptemperatureand4Cconductivitysensors.
Foreachdeploymentthecrewdirectedalldeckoperationsanddrovethewinch,lineswereattachedtotheframetosteadythepackagewhilstitwaseitherliftedoffthedeckoverboard,orliftedondeckinboard.Thetechnicianassistedinthisprocess.Onceinthewater,thecrewloweredthepackagetoaninitialdepthof10m,allowingtheSea-Bird5Tpumpstoprimeandstartoperating.Oncethishadoccurredformostcasts,andwhereweatherallowed,thepackagewasraisedtonearthesurfacethenloweredtoanearbottom.Inputfromthescientificpartydictatedtherequiredbottlestops,andthenumberofbottlestofireateachdepth.Bottleleakagesoccurredonseveralcasts(seecruisenarrativefordetails),buttheseissuesweresolvedbyreplacingbottlesandspareparts.Otherwise,therewerenofurtherissueswithhardware.RefertoNMFtechnicalreportforfurtherdetails.
Uponcompletionofthecastthepackagewaseitherlandedondeck,movedintothehangerandstowedintheCTDdeckplateforthescientiststocommencesampling.Duetotheconfigurationoftheliftinghoistandslowoperatingspeed,thistypicallyaddedafive-minutedelaytothescientistsbeforetheywereabletostarttheirsampling.
BetweenstationssensorswereflushedwithMilli-QandthewholeCTDrinsedwithfreshwatertopreventsaltcrystalsforminginthesensors,associatedtubingandcarousal.
Immediatelyaftereachcasttherawdatawasbackeduptothenetworkdrive,toreducetheriskofdatalossandtomakethedataavailabletothescientificparty.
BasicSea-BirdprocessingoftherawdatathentookplacebyNMFtechniciansusingSea-BirdDataProcessingsoftware.ThefullBODC“RecommendedstepsforbasicprocessingofSBE-911CTDdata.”Version1.0October2010wasfollowedforallcasts.Bottledatawereprocessedproducingaverage,standarddeviation,minimumandmaximumofdatafrom2.5secondsbeforeandafterbottlefiring(5secondtotal).TheCTDdatawasadditionallyusedtoproduceaSBEDataProcessedSoundVelocityProfile(SVP)ineachmainsite.
FIGURE22:CTDDEPLOYMENT,SHOWINGLADPCSANDOTHERSENSORS.PHOTOK.HENDRY.
41
DY081CRUISEREPORT
LADCPTwoLADCPsweremountedontheCTDrosette(Figure22):Master(downwardlooking,attachedtobaseofframe)andSlave(upwardlookingattachedtooutsideofframe).EachcastthefittedLADCP’sweresetuptologdataviathePCusingapre-configuredscriptfile.TheLADCPsweresetupbeforeeachcastwiththefollowingcommands:
TABLE11:COMMANDFILESFORMASTERANDSLAVELADCPS.
; DY081 Hendry, Bristol. LADCP Master
; Dougal Mountifield
PS0 ; Display System Confuration
CR1 ; Restore Factory Defaults
WM15 ; LADCP Water Mode 15
CF11101 ; Disable Serial Output
EA00000 ; Zero Beam 3 Misalignment
EB00000 ; Zero Heading Bias
ED00000 ; Zero Transducer Depth
ES35 ; Salinty 35PSU
EX11111 ; Earth Coordinates use defaults
EZ0011101 ; Use Heading pitch and roll sensors
TE00:00:01.00 ; 1 Second Minimum Time Per Ensemble
TP00:01.00 ; 1 Second Minimum Time Between Pings
LP00001 ; 1 Ping Per Ensemble
LD111100000 ; Collect and Process all data
LF0500 ; LADCP 5m Blank
LN016 ; LADCP 16 Bins
LS1000 ; LADCP 10m Bins
LV250 ; LADCP 250cm/s Ambiguity Velocity
LJ1 ; LADCP High Receiver Gain
LW1 ; LADCP Narrow Bandwidth
LZ30,220 ; LADCP Default Bottom Detect and Correlation Thresholds
SM1 ; RDS3 Master
SA001 ; Send Sync Pulse Before Water Ping
SW05000 ; Ping 500ms after Sending Sync Pulse
CK ; Save As User Defaults
CS ; Start Pinging
; DY081 Hendry, Bristol. LADCP Slave
; Dougal Mountifield
PS0 ; Display System Confuration
CR1 ; Restore Factory Defaults
WM15 ; LADCP Water Mode 15
CF11101 ; Disable Serial Output
EA00000 ; Zero Beam 3 Misalignment
EB00000 ; Zero Heading Bias
ED00000 ; Zero Transducer Depth
ES35 ; Salinty 35PSU
EX11111 ; Earth Coordinates use defaults
EZ0011101 ; Use Heading pitch and roll sensors
TE00:00:01.00 ; 1 Second Minimum Time Per Ensemble
TP00:01.00 ; 1 Second Minimum Time Between Pings
LP00001 ; 1 Ping Per Ensemble
LD111100000 ; Collect and Process all data
LF0500 ; LADCP 5m Blank
LN016 ; LADCP 16 Bins
LS1000 ; LADCP 10m Bins
LV250 ; LADCP 250cm/s Ambiguity Velocity
LJ1 ; LADCP High Receiver Gain
LW1 ; LADCP Narrow Bandwidth
LZ30,220 ; LADCP Default Bottom Detect and Correlation Thresholds
SM2 ; RDS3 Slave
SA001 ; Send Sync Pulse Before Water Ping
ST0 ; Wait Indefinitely FOr Sync Pulse From Master
CK ; Save As User Defaults
CS ; Start Pinging
Beforeonecast(CTD12),therewasnocommunicationbetweentheLADCPandthedataloggingcomputer,sonocurrentdatawererecorded.ThiswaspartoftheCTDgridatNuuk,sothecastcontinuedasitwasconsideredthatcurrentdatadensitywasalreadysufficient.ForCTD21,theMasterandSlaveLADCPswereswitched,andthiswasrecordedintheloggingsheets.RefertoNMFtechnicalreportforfurtherdetails.
42
DY081CRUISEREPORT
SensorsThefulllistofmountedsensorsisasfollows:
TABLE12:LISTOFSENSORSMOUNTEDON24-WAYSTEELCTDROSETTE.
Instrument/Sensor:
Model:
SerialNo:
Channel:
CastsUsed:
Stainlesssteel24-wayframe
NOCS SBECTD1 N/A Allcasts
24-wayCarousel SBE32 32-0423 N/A AllcastsPrimaryCTDdeckunit SBE11plus 11p-0589 N/A AllcastsCTDUnderwaterUnit SBE9plus 09p-0943 N/A Allcasts
PrimaryTemperatureSensor
SBE3P 3p-2729 F0 Allcasts
PrimaryConductivitySensor
SBE4C 4c-3258 F1 Allcasts
DigiquartzPressuresensor Paroscientific 110557 F2 AllcastsSecondaryTemperatureSensor
SBE3P 3p-4816 F3 Allcasts
SecondaryConductivitySensor
SBE4C 4c-2165 F4 Allcasts
PrimaryPump SBE5T 05-3085 N/A AllcastsSecondaryPump SBE5T 05-7371 N/A AllcastsDissolvedOxygenSensor SBE43 43-2818 V0 AllcastsDissolvedOxygenSensor SBE43 43-2575 V1 AllcastsAltimeter Benthos916T 59494 V2 AllcastsLightScatteringSensor WETLabsBBRTD BBRTD-169 V3 AllcastsPARDown-lookingUWIRR BiosphericalQCP
CosinePAR70520 V4 Allcasts
PARUp-lookingDWIRR BiosphericalQCPCosinePAR
70510 V5 Allcasts
Transmissometer WETLabsC-Star 1602DR V6 AllcastsFluorometer CTGAquatracka
MKIII88-2615-126 V7 Allcasts
10LWaterSamplers OTE 1A-24A N/A AllcastsDown-lookingMasterLADCP(Aluminium)
TRDI/WHM300kHz 1855 n/a n/a
Up-lookingSlaveLADCP(Aluminium)
TRDI/WHM300kHz 23444 n/a n/a
LADCPbatterypackpressurecase
NOCS WH007 n/a n/a
43
DY081CRUISEREPORT
Glideroperations
ConfigurationPriortoloadingonRRSDiscoveryinSouthampton,UKSlocumUnits331and439underwentin-houserefurbishmentandwereballastedfor1027.0at3˚Cinpreparationfordeployment.Thegliderswereconfiguredasinthetablebelow.
TABLE13:CONFIGURATIONOFSLOCUMGLIDERS.
Unit331SlocumTWRFWD:SN:1400153(INV.260002528)SlocumTWRAFT:SN:1400115(INV.260002513)Slocumdeeppump:SN:120(INV.260001982)�G2DigiFin:SN:1467(INV.260000277)Slocumsciencebay(pumpedCT):SN:1115(INV.250008907)AanderaaOptode:�SN:143(INV.250008327)�Firmware:�GliderDos:7.18/SciDos:3.21WETLabspuck:SN:3354(INV.260002075)
Unit439SlocumTWRFWD:SN:1300108(INV.260002521)SlocumTWRAFT:SN:1300100(INV.260002505)Slocumdeeppump:SN:210(INV.260000276)�G2DigiFin:SN:____(INV.26000____)Slocum science bay (pumped CT): SN: 1103(INV.260001980)AanderaaOptode:�SN:243(INV.250002409)�Firmware:�GliderDos:7.18/SciDos:3.21�WETLabspuck:SN:3347(INV.260002070)
DeploymentplanDuetothestrengthanddirectionofprevailingcurrents,adeploymentplanwasfinalisedsuchthatthegliderswouldtravelinanortherlydirection,followingthecurrentwhilsttransectingtheshelfinrepeated‘zig-zags’.RecoverypositionwasanticipatedtobeinapproximatelythemiddleoftheNuuksurveysite.DeploymentwascarriedoutinaccordancewithNMFproceduraloperations,withoutanyissues.
TheunitswerepilotedbySteveWoodward(NOC,Southampton),withCandiceCameronastheonboardtechnician.Theunitsweredeployedfrom62o54.198’N,52o37.816’Won17thJuly2017.Unit331–“Coprolite”–wasdeployedfirst,followedbyUnit439–“HSB”.Theanticipatedrecoverypositionwas63o35.096’N,53o16.663’W.
MissionThepathoftheglidersdifferedfromplannedduetostrongcurrents(Figure23).However,bothglidersrecordeddataonthreecrossingsoftheshelfbreakeach.Seetechnicalreportfordetailsonthemissionandpilotlogs1.
RecoveryRecoverywascarriedouton24thJuly2017at1320(Unit331)and1430(Unit439)GMTinaccordancewithNMFguidelinesand,despitepoorglidervisibilityduringthesearch,thegliderswereeventuallylocatedandrecoveredsafelyondeckwithoutfurtherissue.SeeFigure24.
1MARS–GlidersExpeditionReportforDY081:ICY-LAB,C.Cameron.2017.
44
DY081CRUISEREPORT
FIGURE23:MAPOFGLIDERROUTESONDY081.
45
DY081CRUISEREPORT
FIGURE24:RECOVERYOFGLIDERUNIT331‘COPROLITE’.THETOWLINEINTHENOSECONEISUSEDTOWINCHTHE
GLIDERVERTICALLY,BEFOREBEINGLOWEREDONTODECKANDSECURED.PHOTOSBYK.HENDRY.
46
DY081CRUISEREPORT
RemotelyOperatedVehicleoperations
TheRemotelyOperatedVehicle(ROV)–Isis–wasdeployedtocollectsedimentsamplesfromglaciatedregions,whereconventionalcoringmaybeinappropriate,andtocollectsamplesforcomplementaryprojects.Diveplansandmapsweregeneratedpriortoeachlaunch,tosuittheobjectivesofthespecificdive.
Generaldescription
• Depthrated6500m• ROVistetheredtoshipwithhighvoltage,opticfibrecableforrealtimevideofeeds• Twomanipulatorarms(Kraft(port)andSchilling(starboard))• “Slurp”suctionsystemandnetsforsamplecollection• Mainbiobox,biotubes,pushcores,netsonthefronttray,withportandstarboardbioboxes,andsix1.7L
Niskinsbottes,five“slurp”chambersattherear(seeFigure25)• ASeabird49CTDisattachedtotheROVframeanddataarerecordedthroughoutthedive;processingof
therawCTDdatathentookplacebyPSOusingSea-BirdDataProcessingsoftware• Threehighdefinitionvideocamerasareattached:HDSci(onpan-tiltmodule,controlledbyleadscientist),
HDPilot(onpan-tiltmodule,controlledbypilot)andScorpio(fixedview,with4672x2628(16:9Format)stillstakentypicallyevery30seconds);lowerdefinitionmini-cams(uplook,drawer,sampler/gauges)andlow-definitionMercurymonochromeaftcameraarealsoattached;aftcameraalsorecordedonPALonoccasion
• AllvideosarerecordedontoKiProtapes,with2hourintervalsthensavedontoMasterandBackupLaciedrives
• LaserswereattachedtoScorpioandHCSciat10cmspacing• ROViscontrolledfromvanwithtwopilotsandleadscientistatfrontconsole,and2-3otherobserversat
therearconsole• LoggingiscarriedoutonhardcopyandusingOFOPloggingsoftware• Navigation,Sensor,andstillsarealsocopiedontoaMasterandBackupLaciedrives,andNavigation,
Sensor,ScorpioimagesandvideowereadditionallybackedupasaworkingcopyonafurtherLaciedrivefortheUniversityofBristol
FIGURE25:EXAMPLEOFROVTRAYCONFIGURATIONFROMROVDIVE337.
47
DY081CRUISEREPORT
TABLE14:TABLEOFLOCATIONSOFROVDEPLOYMENTS;OK=ORPHANKNOLL;SG=SOUTHERNGREENLAND.
Note:a=ROV331andROV337wereaborted;ROV334wasaMultibeamresondiveandnoScorpioimagesareavailable
Site Station Gear JdayStart
StartTime(GMT)
StartLat(DD)
StartLon(DD) Startwaterdepth(m)
JDayEnd
EndTime(GMT)
EndLat(DD)
EndLon(DD)
Endwaterdepth(m)
OK 5 ROV327 189 16:19:00 50.04158 -45.37940 3550.8 190 18:01:00 50.0832 -45.3594 1941.0
OK 7 ROV328 191 07:50:00 50.55481 -46.19323 1669.2 191 16:21:00 50.5564 -46.1956 1576.7
OK 8 ROV329 191 20:48:00 50.55182 -46.19227 1792.0 192 17:28:00 50.5698 -46.1836 1527.0
OK 11 ROV330 192 23:23:00 50.55118 -46.19071 1825.5 193 12:00:00 50.5512 -46.1934 1717.0
OK 13 ROV331a 193 16:15:00 50.50629 -46.08250 1848.0 194 06:24:00 1586.0
Nuuk 30 ROV332 201 02:45:00 63.86858 -53.28953 964.0 201 03:06:00 63.8704 -53.2901 950.0
Nuuk 31 ROV333 201 03:49:00 63.86612 -53.28869 970.0 201 23:11:00 63.8657 -53.2834 805.0
Nuuk 34 ROV334b 202 07:00:00 63.86511 -53.28258 807.0 202 16:05:00 63.8651 -53.2784 683.0
Nuuk 36 ROV335 203 03:38:00 63.33217 -52.77710 1281.0 204 03:32:00 63.3317 -52.7550 898.0
Nuuk 37 ROV336 204 10:51:00 63.60375 -52.91897 515.0 204 20:53:00 63.6112 -52.9032 345.9
SG 44 ROV337a 207 17:33:00 60.09451 -47.31853 1037.2 207 20:19:00 60.1063 -47.4009 1048.0
SG 50 ROV338 208 18:46:00 60.09000 -46.62533 603.50 209 18:12:00 60.0862 -46.6497 1064.0
SG 52 ROV339 210 07:04:00 59.94672 -46.54810 1148.0 210 21:46:00 59.9423 -46.5069 589.0
48
DY081CRUISEREPORT
SeeAcousticsOperationssectionfordetailsonresonsettingsfordiveROV334.
SeeROVtechnicalreportforfurtherinformationonthevehicle’stechnicalperformance2.
FIGURE26:RECOVERYOFROVDIVE338.PHOTOSBYVEERLEHUVENNE.
FIGURE27:ROVDIVESITE327(OVERTHEPAGE).PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF50˚N.
FIGURE28:ROVDIVESITE328-330.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF50˚N.
FIGURE29:ROVDIVESITE331.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF50˚N.
FIGURE30:ROVDIVES333AND334.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF63˚N.
FIGURE31:ROVDIVE335.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF63˚N.
FIGURE32:ROVDIVE336.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF63˚N.
FIGURE33:ROVDIVE338.PRODUCEDINMERCATORPROJECTIONWITHASTANDARDPARALLELOF63˚N.
2IsisROVSystem:ExpeditionReport.RRSDiscovery(DY081).D.Turner.2017.
49
DY081CRUISEREPORT
Figure27
50
DY081CRUISEREPORT
Figure28
51
DY081CRUISEREPORT
Figure29
52
DY081CRUISEREPORT
Figure30
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63°5
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63°5
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0 0.1 0.2Nautical Miles
0 0.2 0.4Kilometers
DIVE 333 and 334
50 metersBathymetry
100 m900 m1400 m2200 m
Projection: World Mercator, Standard Parallel = 63 Degrees North
_̂ GRB!@ NET$ NSK# PSHÅ SLP
Dive 333
Dive 334
53
DY081CRUISEREPORT
Figure31
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52°45'W52°45.5'W52°46'W52°46.5'W
63°2
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63°1
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0 0.25 0.5Nautical Miles
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54
DY081CRUISEREPORT
Figure32
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52°53'W52°54.5'W52°55'W
63°3
6.5'N
63°3
6.5'N
63°3
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63°3
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0 0.25 0.5Nautical Miles
0 0.4 0.8Kilometers
Dive 336
50 metersBathymetry
100 m900 m1400 m2200 m
Projection: World Mercator, Standard Parallel = 63 Degrees North
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55
DY081CRUISEREPORT
Figure33
56
DY081CRUISEREPORT
SAPsoperations
Standalonepumps(SAPs)weredeployedtocollectparticlesfromthewatercolumntoaddressthekeyquestionsoftheresearchprojectandforotherbiogeochemicalresearch.FourSAPswereavailablefortheexpedition:“Minnie”(S/N88395331),“Chloe”(S/N94K004003),“Sandie”(S/N01K000394)and“Polly”(S/N94K004001).Ateachstation,oneortwopumpsweredeployedattwodifferentdepths,witheitheraGlassFibreFilter(GFF)orSupor0.45µmfilterfittedintopancakefilterhousings.TheSAPswereclampedtoCTDwire(Figure34)andweigheddown,initiallywith100kgforthefirstdeployments,thenwiththe500kgweighttohelpwithdeploymentspeed.Thepumpswereprogrammedtopumpfor1.5hoursatdepth,thenrecovered.
TheSAPswereeachfittedwithaSeabird39(SBE39-6756)andastrain-gaugepressuresensor.BasicSea-BirdprocessingoftherawdatathentookplacebyNMFtechniciansusingSea-BirdDataProcessingsoftware.
ThereweresomeminorissuesthatarosewiththeSAPs,mainlysurroundinghousing“Minnie”(seecruisenarrativefordetails).Despitetheseproblems,onlyonefilterwassignificantlycompromised(SAP05“Chloe”).RefertoNMFtechnicalreportforfurtherinformation.
FIGURE34:RECOVERYOFSAPS.PHOTOBYK.HENDRY.
57
DY081CRUISEREPORT
Towfishoperations
TheTowfishwasusedtocollectuncontaminatedwaterfortracemetalsampling,andwaskindlyloanedtousbyProfEricAchterbergofUni.SouthamptonandGEOMARinKielfollowingDY080.Thesystemconsistsofaweightedfishloweredintothewaterasfarfromtheshipaspossible~5mbelowthesurface.Thefishholdsalengthofacid-cleanedtubingconnectedtoanair-poweredpumpondeck.Theglider-shapedfishkeepsthetubingpointedintocleanwaterandawayfromtheship,andflowisdirectedintothecleanchemistrylabforsampling.
DeploymentsweredonewiththehelpofthecrewandNMFtechnicians,keepingtheopenendofthefishtubingcoveredasmuchaspossibletopreventcontamination.TheTowfishwasdeployed6timesonDY081(Table15)fromthecraneontheportsideoftheaftdeck.
TABLE15:DEPLOYMENTOFTHETOWFISHDURINGDY081.
Gearnumber
Timein Lat/Long Timeout Lat/Long
FSH01 9/7/1718:10
50.08318 -45.35940
10/7/1707:20
50.5528 -46.1944
FSH02 13/7/1707:11
50.50770 -46.08840
19/7/1722:19
50.5755 -45.9865
FSH03 20/7/1723:23
63.86599 -53.28424
21/7/1704:51
63.9535 -52.9167
FSH04 23/7/1721:05
63.61123 -52.90324
26/7/1716:34
60.0941 -47.3158
FSH05 26/7/1720:30
60.11090 -47.41771
27/7/1717:14
60.0898 -46.6496
FSH06 29/7/1722:07
59.94239 -46.50713
31/7/1719:18
59.9395 -43.7783
Whilstthefishwasinthewater,thepumpwasleftoncontinuously.Samplingfortracemetalswasperformedonlywhentheshipwasmovingat>0.5kts.Whenstationaryandwhenevertheuncontaminatedwatersupplywasnotbeingsampledfortracemetals,thewaterwasdirectedoutofthecleanlabandintothehangar,whereitcouldbesampledforradiumisotopesorwasdrainedviathedeckdrains.
58
DY081CRUISEREPORT
Chapter6:PhysicaloceanographyIntroduction
PhysicaloceanographicstudieswerecarriedoutonDY081,tocharacterisethewatercolumnstructureineachlocation,specificallytolocateandquantifythefreshwaterinputsintheGreenlandsites.ThesedatawillhelpusunderstandtheoceanographicpathwaysofwatermassesintheLabradorSea,andassesstheimpactoffreshwaterinputsonthebiogeochemistryofWestGreenland.
PhysicaldatawereobtainedusingrosetteandROVmountedsensors,glidermountedsensors,andwatercolumnacoustics(tobeprocessedonshore).
Geochemicaldatawillbeusedtosupportthephysicalsensordata(SeeChapter7).
SummaryofsensordeploymentsandpreliminaryresultsSensordatafromCTDrosettes
PreliminaryresultsfromOrphanKnollCTDprofilesshowedsub-thermoclinewarm,salinewaterswereunderlainbyLabradorSeaWaterandlikelyoverflowwaters.ThewatercolumnstructurewasmorecomplexoverOrphanKnollitself,likelyillustrativeofmesoscaleprocesses(Figures35,36).
FIGURE35:T-SPLOTFROMORPHANKNOLL.
FIGURE36:CTDDEPTHPROFILESFROMCTD01ORPHANKNOLL(OVERTHEPAGE).
59
DY081CRUISEREPORT
Figure36
PreliminaryresultsfromNuukFollowingarelativelyopenoceanCTDcast(CTD03)tothesouthofthestudyarea,furtherCTDcastsinthestudyareaformedagridtocovertheoff-slope,slope,andshelfregionsofthearea,toinvestigatefreshwatersupplyandtransportfromGreenland.ThefirstlineofthegridwasdesignedtooverlapwiththeFyllaBankline(e.g.Stein&Buch,1991),withthesouthern-mostlinecoveringaglacialtrougharea.
1) GeneralstructureillustratedbyCTD03tothesouthofthisstudyareaandCTD004(Figure37):Cold,subsurfacewaterisfoundat<100m,overlyingastrongthermocline;AtlanticWater(T>3˚C,salinity<34.5)isfoundbelowthethermocline;temperaturepeakingatapproximately400m,mostlikelythecoreofIrmingerWaterinflowfromEastGreenland.
2) Shelfareatonorth(FyllaBank)generallywellmixed:athermoclineispresentatapproximately40matpoint2.3(CTD11),butabsentinpoint1.5,CTD14(Figures38,39).
3) Analysisofthesouthernportionofthegridindicatesmid-waterpolarwaterinputs,whichwerethentargetedforSAPSdeployment.Layersofcold,marginallyfresherwaters(alsoassociatedwithhigherturbiditypeaks)areobservedatapproximately220and420matpoint3.3(CTD10).Theselayersarealsoobservedatsimilardepths(slightlydeeper)atpoint2.2(CTD12),suggestingtheinputfromthetroughflowswestwardintotheboundarycurrentandiscarriednorth(Figure38;supportedbyLADCPdata,seebelow).
4) Highproductivityatallsitesresultedinhighturbidityinsurfacewaters.PARdeclinedrapidly,generallyat0%by15-40m.Subsurfacepeaksinturbiditywereobservede.g.atapproximately160-170mdepthinCTD16,whichwerealsotargetedforSAPSdeployment.
FIGURE37:DEPTHPROFILE(OFFSLOPE)FORCTD04(OVERTHEPAGE).
FIGURE38:TEMPERATUREANDSALINITYPLOTSFORCTDGRID,PLOTTEDWITHBATHYMETRYDATA.
61
DY081CRUISEREPORT
Figure37
0
500
1000
1500
2000
2500
3000
3500
4000
De
pth
[D
ep
Sm
]
34 35Salinity [Sal11; psu]
2017 Jul 20 06:29:23 DY081_CTD004_DATCNV_Filter_AlignCTD_CellTM_LoopEdit_Derive_down_1m_strip.asc
0.0 0.5 1.0 1.5Fluorescence [FlC; ug/l]
0.0000 0.0005 0.0010Turbidity [TurbWETbb0; m^−1/sr]
0
500
De
pth
[D
ep
Sm
]
3 4 5 6 7
Temperature [T190C; degC]
260 280 300 320 340 360
Oxygen [Sbox0; Mm/L] DY
081_019_
CT
D04
62
DY081CRUISEREPORT
Figure38
FIGURE39:T-SPLOTSFORNUUKCTDS.
PreliminaryresultsfromSWGreenlandTwoadditionalglacialtroughswereidentifiedatthesoutherntipofGreenland,andwerestudiedasadditionalcasestudiesforfreshwatersupplyandroutingfromtheshelfofftheslope.ShortertransectsofthreeCTDs(offslope,onslopeandshelf)wereplannedineachoftheselocations,nearNarsaqandCapeFarewellrespectively.
Agenerallytypicalopenoceanprofilegavewaytoprofilescharacterisedbyverylowsalinitysubsurfacepolarwatersoverlyingwarmer,AtlanticwatersinregionstowardsshorenearNarsaq;lowsalinitysurfacewaterswerealsoencounterednearalikelysea-iceedgeonCapeFarewell(Figures40-42).
FIGURE40:DEPTHPROFILEFORCTD17(OFFSLOPE,NEARNARSAQ).
FIGURE41:DEPTHPROFILEFORCTD19(ONSHELF,NEARNARSAQ;NOTETHELOWSALINITYSURFACEWATERS).
64
DY081CRUISEREPORT
Figure40
65
DY081CRUISEREPORT
Figure41
66
DY081CRUISEREPORT
FIGURE42:T-SPLOTFORALLCTDDATAFROMNARSAQANDCAPEFAREWELL.
LADCPdatafromCTDrosetteRawLADCPdatafileswereprocessedwiththeLDEOLADCPprocessingsoftwareversionIX_8,whichwasrunon
Matlab.TheprocessingversionwassettobottomtrackingmodeandemployedauxiliaryCTDtimeseriesdata.
ProcessedCTDprofilefilesalsoincorporatedGPSdatastoredparallelintime,arrivingfromtheship’s1Hzfeed.
PairingtheCTDprofiledatawiththeLADCPcastsintimeisexecutedbycorrelatingthepressuretimeseriesofthe
CTDfilewiththedepthoftheLADCPcast,itselfcalculatedthroughintegrationoftheverticalvelocity.Shipboard
ADCPdatawerenotincludedintheprocessingprocedure.Throughouttheprocessingtask,therewereonly
intermittentandminorissueswiththecastsflaggedupbythesoftware.Onewarningconsistentlygeneratedafter
cast14was=‘nofixedpingingrate’.Thiswarningwasdeemednoteworthybutinsignificant.
Tocustomisetheinput,thescript‘set_cast_params_v4.m’wasusedasatemplatethatwasmodifiedaccordingly.
Here,thedown-lookingandup-lookingLADCPfileswereselectedandtheoutputfilepathsset.TheCTDinput
datawerethe2Hz.cnvfileswithheaderintact.Onceallthenecessarymodificationsweremade,
‘process_cast_v4.m’wasranwiththestationnumberastheonlyargument.Runningthiscodeautomatically
saved14figuresin.psformataswellotheroutputloggingfilesandtheverticalprofilessavedina.ladfile.All
processedfilesforeachcastwerestoredinthecruisedriveinthedirectory:
‘/Volumes/public/DY081/LADCP_processing’.
DifficultieswereencounteredfortheCTDstationsnearNuukinwaterswithabottomdepthshallowerthan100m
(station11andstation14).Herethesurfaceandbottomechointerferenceresultedinabrokencodeandno
inversesolution.TherewerealsoissueswiththecastfromCTDstation22.Here,thevelocitymagnitudeswere
impossiblyhigh.Uponinspection,theerrorseemstooriginatefromthelackofcorrelationfoundbetweenthe
CTDandLADCPprofiledata,sotheCTDprofileisdiscardedresultinginanendcoordinateof0oN0oW.Scrutinising
theCTDinputfileyieldsnoobviousreasonforthesecorrelationissues.Itmayberelatedtodiscontinuitiesinthe
67
DY081CRUISEREPORT
CTDtimeseriesonthecastascent–withsamplinggapslongerthan2minutes.Forthetimebeing,thisLADCP
castwasranthroughtheprocessingsoftwarewithoutauxiliarydata.
PreliminaryLADCPresultsareshowninFigures43and44.Figure43showsLADCPvelocityinaCTDlinebetween
station8(63.418oN’-53.15oW)andstation16(63.58oN’-52.15oW),withstations9,10and15intheinterior,
collectedovera5-dayperiod.Figure44showstheLADCPvelocityprofileatstation16producedbytheLDEO
softwarecarriedoutfollowingthestepsoutlinedabove.
FIGURE43:ZONAL(TOP)ANDMERIDIONAL(BOTTOM)VELOCITYATTHECTDSECTIONNEARNUUK.YELLOWINVERTEDTRIANGLESARE,FROMLEFTTORIGHT,THECTDSTATIONS8-10AND15-16.THEBATHYMETRYWASOBTAINEDFROMTHE
MULTIBEAMDATAGATHEREDDY081.
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DY081CRUISEREPORT
FIGURE44:THEPROCFIG1OUTFROMLDEOPROCESSINGSOFTWARESOLUTIONFROMCAST#16WITHVERTICALVELOCITYINTHELEFTPANEL.VELOCITYCOMPONENTSAREMERIDIONAL(GREEN)ANDZONAL(RED)ANDVELOCITYFROM
BOTTOMTRACKINGISBELOWINTHEBOTTOMLEFTPANEL.TOPRIGHTPANELCONTAINSMETADATAANDKEYPARAMETERSUSED.CENTRERIGHTPANELGIVESTHETARGETSTRENGTHANDRANGEOFINSTRUMENTSANDBOTTOMRIGHTISTHEPOSITIONOFTHE
SHIPANDINSTRUMENTDURINGTHECAST
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DY081CRUISEREPORT
InstrumentationandsensorsonothertetheredequipmentAdditionaltemperature,salinityanddepthdatawereprocessedfromboththeSAPs(temperatureonly)andROV
CTD.Thedatawillbeusedforthemainprojectasadditionalconstraintsonwatercolumnstructure,andby
complementaryprojects.Theresultshighlightthedynamicnatureofthestudyareas(e.g.Figure45).
ShipboardADCPdatawillbecalibratedandworkeduponshore.
FIGURE45:EXAMPLET-SPLOTFORROVCTDDATA,COMPAREDTONEARBYCTDROSETTEDATA,FROMORPHANKNOLL.
Summaryofgliderdeployments
Gliders(NMFSlocumgliders,units331and439)weredeployedintheNuukregiontoobtainhighspatialand
temporalinformationaboutthewatercolumnstructure,specificallythetransportoffresherwateroutofthe
shelfregionandacrosstheslope.Theplannedgliderpathscoveredtheshelfbreak,severaltimes,andthemouth
ofthemainglacialtrough.
AsperNMFprotocol,thegliderswerenotopenedatsea,anddatawillbedownloadedoncereturnedtothe
workshopinSouthampton.Preliminarydatatransmittedbytheglidersshowthatcolder,fresherwaters,were
captured,inadditiontovariabilityinchlorophyllcontentandturbidity.
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DY081CRUISEREPORT
Chapter7:WatersamplingIntroduction
WatersamplesarebeingcollectedaspartofDY081,toquantify:1)freshwaterinputs(seeChapter6);2)nutrient
concentrationsandfluxes;3)nutrientisotoperatios;andtocarryoutothercomplementaryprojects.Particulates
werecollectedforbiogenicsilica,chlorophylla,andotherpigmentsinsurfacewaters,tohelpquantifythe
productionofsiliceousorganisms.
Summaryofwatersamplingevents
TABLE16:CTDWATERSAMPLINGEVENTSDURINGCRUISEDY081(OVERTHEPAGE).
TABLE17:MEGACOREWATERSAMPLINGEVENTS.
TABLE18:ROVWATERSAMPLINGEVENTS.
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DY081CRUISEREPORT
Site Gearno.
Events(Niskins)
CO3 DI14C Nuts d30Si d14N U-ser d18O StableNd
RadNd Sal BSi Chla POC/PON
OrphanKnoll
CTD01
24 12 12 12x2 12 12x2 12x2 12 6 5 4 1
OrphanKnoll
CTD02 24 8 8 8x2 8x2 3 8 4 8
Nuuk CTD04 24 12 12 12x2 12 12x2 12x2 12 12 7 4 7Nuuk CTD05 24 12x2 12 12x2 12x2 12 4 4 4Nuuk CTD06 24 11x2 11 11x2 11x2 4* 11 4 4 4Nuuk CTD07 24 8x2 8 8x2 8x2 8 4 4 4Nuuk CTD08 24 12x2 12 12x2 12x2 3* 12 4 4 4Nuuk CTD09 24 12x2 12 12x2 12x2 12 4 4 4Nuuk CTD10 24 8 8 8x2 8 8x2 8x2 8* 8 4 4 4Nuuk CTD11 24 8x2 8 8x2 8 4 4 4Nuuk CTD12 24 12x2 12 12x2 12 4 4 4Nuuk CTD13 24 12x2 12 12x2 12 4 4 4Nuuk CTD14 24 12x2 6 12x2 12x2 1 12 12 12 12Nuuk CTD15 24 12x2 12x2 12 4 Nuuk CTD16 24 12x2 8 12x2 12 5 SGreen CTD17 24 12 12 12x2 12 12x2 12x2 2 10 12 7 SGreen CTD18 24 12x2 12 12x2 12x2 3 4 12 4 4 4SGreen CTD20 24 12 12x2 12x2 3 4 4 SGreen CTD21 24 12x2 12 12x2 3 4 4 4SGreen CTD22 24 12x2 12 12x2 12x2 12 12 4 4 4SGreen CTD24 24 12x2 12 3 12x2 12 5 5 5
*RadiogenicNdsamplesplitsforU-serieswork
CO3=carbonatechemistry;DI14C=dissolvedinorganicradiocarbon;Nuts=nutrients;d30Si=dissolvedsiliconisotopes;d15N=nitrogenisotopes;U-ser=uraniumseriesisotopes;StableNd=stableneodymiumisotopes;RadNd=radiogenicneodymiumisotopes;Sal=salinity;BSi=biogenicsilica;Chla=chlorophylla,b,c;POC/PON=particulateorganiccarbonandnitrogen
Table16
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DY081CRUISEREPORT
Site Gearno. Events(Niskins)
Nuts d30Si d14N RadNd
OrphanKnoll
MGA01† 1 1x2 1 1x2
OrphanKnoll
MGA02† 1 1x2 1 1x2
Nuuk MGA03† 0 Nuuk MGA04† 1 1
SGreen MGA05 1 1
SGreen MGA06† 1 1
SGreen MGA07† 0
†Coretopwateralsosampledfornutrientsandsilicon/nitrogenisotopes
Table17
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DY081CRUISEREPORT
Site Gearno.
Events(Niskins)
CO3 Nuts d30Si d18O
OrphanKnoll
ROV327 6 2x2
3
4 2
OrphanKnoll
ROV328 6 2x2 2 1x2
OrphanKnoll
ROV329 6 3x2 3 3x2
Nuuk ROV333 3 3x2 3x2
Nuuk ROV335 6 3x2 3x2 3x2
Nuuk ROV336 6 3x2 3x2 3x2
SGreen ROV338 6 2 2 2x2
SGreen ROV339 3 2 2
Table18
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DY081CRUISEREPORT
SummaryofICY-LABprojectseawaterparameters
Parameters,listedintheorderofcollectionfromtheNiksinrosette
1. Dissolvedoxygen
NotethatcalibrationofbottledatawithCTDoxygensensorswasbadduetotitratorfailure,andnofurtherbottleoxygenanalysiswascarriedoutbytitrationafterOrphanKnoll.Protocolfollowedisgivenbelowforreference.
Priortofirstuse,thePVCtubeshouldbesoakedincleanseawaterforatleastonedaytopreventbubbleformation.ThePVCtubingisplacedovertheNisinoutletvalve.Asmallvolumeofseawaterisrunthroughtoremoveair.A250mLglassbottleisrinsed3timeswithseawaterfromtheNiskinbottlebeforebeingfilledandallowedtooverflowforabouttwicethevolumeofthebottle.Carewastakentoavoidbubblesinsidethesamplingtubeandbottle.Thetemperatureofthewaterwasimmediatelyrecordedto0.1˚Cusingahandheldthermometer.MnCl2andNaOH/NaI(1mLeach)isaddedimmediatelytoseawaterusingbottle-topdispensingpipettes,beforestopperingthebottle.Inthelaboratory,thebottleisswirledtomixtheprecipitates,andthegaparoundthestopperisfilledwithunfilteredsurfaceseawatertocreateawatersealtopreventevaporationandbubbleformation.Thesamplesarestoredatroomtemperatureinthedark,andanalysedwithin12hoursofcollection.
2. Carbonatechemistry
Carbonatechemistryparameters(pH,alkalinity)canbeusefulparametersininvestigatingfreshwaterinput,andareusefulforanumberofcomplementarystudies(e.g.growthofscleractiniancorals).
A250mLborosilicateglassbottleisrinsedtwicewithseawaterfromtheNiskinbeforebeingfilledusingaPVCtubeandallowedtooverflowonevolume.Theglassstoppedisplacedin,todisplaceexcessseawater;another2.5mLofseawaterispipettedofftoallowa1%headspace.Thesampleispoisonedwith50µLsaturatedmercuricchloridesolution.ThebottlestopperissealedusingApiezonLgrease,andtapedwithelectricaltape.Thesampleishomogenisedandstoredinacool,darkplace.
CarbonateanalysiswillbecarriedoutinGEOMAR,Germany.ForTDICcarbonatespeciesareconvertedtoCO2byadditionofphosphoricacid(10%in0.7MNaCl),thisgeneratedCO2isthencarriedintothemeasurementcellusingN2andanalysedbycoulometrictitrationusingaVINDTA3C(Marianda,Germany)connectedtoa5011coulometer(UIC,USA).ForTAsamplesaretitratedwith0.1MHCl(preparedin0.7MNaCl)in150μLincrementsuntilthecarbonicacidequivalencepointisreached.ThetitrationismonitoredwiththeVINDTA3Cinaclosedcelltitration(Dickson,SabineandChristian,2007)
Thetemperature,salinityandnutrientconcentrationsofthesamplesattimeofsamplingarethencombinedwiththeTDICandTAmeasurementstocalculateCO2systemparameters.
3. Radiocarbon
Theradiocarboncontentwillbeusedtodeterminetheageofthewaters.
Rinsea250mLglassbottleandcapthreetimes,withseawaterfromtheNiskinviaadedicatedsiliconetube.Thebottleisfilledandallowedtooverflowonevolume.Thesampleispoisonedwith25µLsaturatedmercuricchloridesolution,sealedandhomogenised.Theglassbottleishandledwithcare,andonlyplacedonclean,newplastic.Thebottleisstoredinaplasticbag,inacool,darkplace.
Theradiocarboncontentofdissolvedinorganiccarbonwillbeanalysedatalaterstage.
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DY081CRUISEREPORT
4. Nutrients
NutrientmeasurementsareakeycomponentoftheICY-LABproject.Thesamplesweretakenwhilstwearingvinylglovesonly,andtakeninduplicate.ThebottleswererinsedthreetimeswithseawaterfromtheNiksin,filteredusingeitheranAcropakorinlinefilter(0.2µm)3.Headspaceisleft,andthesampleisfrozenat-20˚C.
Thenutrientswillbeanalysedbackashorebyusinga5-channelsegmentedflowautoanalysermadebyBranandLuebbe,andwithhighresolutioncolorimeters,thenutrientsanalysedwillbeNitrate+Nitrite,Nitrite,Silicate,PhosphateandAmmonium(Brewer&Riley,1965;Grasshoff,1976;Mantoura&Woodward,1983;Kirkwood,1989;Zhang&Chi,2002).Sampleswillbedefrostedfromfrozenandthebottleswashedanddriedtoensurenocontaminationonopeningthebottlesfromoutsideinfluences.Sampleswillbeanalysedalongwithanutrientreferencematerial(KANSOTechnos,Japan)thatwillbesampledtoensurecorrectcalibrationsaremadeandtoactasacrossreference.
5. Siliconisotopes
Siliconisotopes(denotedbyd30Si)provideinformationabouttheprocessesinvolvedinthesiliconcycle,andsoareakeycomponentoftheICY-LABproject.ThebottleswererinsedtwicewithseawaterfromtheNiksin,filteredusingeitheranAcropakorinlinefilter(0.2µm).Thebottlesarestoredinthecoolanddark.
SiliconisotopeswillbeanalysedonshoreusingamethodadaptedfromdeSouzaetal.,2012,intheBristolIsotopeGroup,UniversityofBristol.Briefly,seawaterwillbeprecipitatedusingsodiumhydroxide,beforebeingredissolvedandchemicallypurifiedusingcationexchangeresin,andanalysedusingaMulti-CollectorInductivelyCoupledPlasmaMassSpectrometer(ThermoNeptuneMC-ICP-MS).
6. Oxygenisotopes
Wateroxygenisotopes(denotedbyd18O)areusedinfreshwaterbudgetcalculations,andsoareakeycomponentoftheICY-LABproject.60mLofunfilteredseawateraresampledcleanlyinduplicate,sealedandstoredincoolstow.
ThesampleswillbemeasuredattheNERCIsotopeGeosciencesLaboratory,NIGL,usingtheVGSIRA(withisoprep18)massspectrometersystem.
7. Salinity(bottle)
Bottlesalinitiesweremeasuredforfreshwaterbudgetcalculations,byNMFtechnicians(seebelowandtechnical
reportforfurtherinformation).Unfilteredwatersamplesarecollectedinglassbottlesandsealedwithaplastic
stopperandmetalcapformeasurementonboard(seebelow).
8. Uraniumseries
Uraniumseriesisotopescanbeusedtoinvestigateweatheringprocesses,andsoareanimportantpartoftheICY-LABproject.5litresofwaterwerefilteredleanlythrough0.2µmAcropakorpolycarbonateinlinefilterandacidifiedto0.1%v/vhydrochloricacid(RomilUpA).ThesampleswerestoredincoolstowforanalysisintheUK.
UraniumseriesisotopeswillbeanalysedattheUniversityofBristolfollowingAuroetal.,2012.
3Giventheyhavethesameporesize,thesetwofiltertypeswereusedinterchangeablyinallcasesoffilteringwiththeexceptionofPOC/PONandchlorophyll.
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DY081CRUISEREPORT
9. Particulates
Remainingwaterwasfilteredforbiogenicsilica(polycarbonatefiltersdriedandsealed),chlorophylla,b,andcanalysis(GFFfilters,seeshipboardanalyses),POC/PON(GFFfilters,flashfrozenat-80˚Candstoredat-20˚C)andphytophysiologyexperiments(seeshipboardanalyses).Volumespassingthrougheachfilertypewerelogged.
Particulatebiogenicsilicawillbeanalysedafteralkalineextractionusingaphotospectrometricmethod,followingDemasteretal.,1981.POC/PONwillbeanalysedbyDrSianHenley,UniversityofEdinburgh.
Sampleswereinitiallycollectedforphytophysiologicalresearch,butthePulseAmplitudeModulation(PAM)devicedidnotfunctionduringthecruiseandnodatawerecollected.OnthefirstrunthePAMwasexhibitingproblemswiththesaturatingpulse.Aftertroubleshooting,itwasdeterminedthatthebatterywasfriedandwasnotchargingtothepropervoltage.Afterreplacement,thegainwasstilltoohighandtherewasnoriseinyieldfromfluorescencebeforethesaturationpulsetotheyieldreachedduringthelastsaturationpulse.Afternumeroustriestogetthedetectorworkingandtroubleshootingotherproblems,itwasbelievedthatthedetectorwasfriedandthesaturatingpulsewasnotworkingcorrectly.SampleswerenolongercollectedforPAManalysis.
SomeadditionalsurfacesampleswerefilteredforSEMimagingofdiatomassemblagesatCardiffUniversity,andstoredundercool,darkconditions(Williams,Cardiff).
TABLE19:TABLEOFSAMPLESTAKENFORDIATOMIMAGING.
Site StationNo GearNo Niskinbottlesfiltered
Nuuk 19 CTD004 20Nuuk 19 CTD004 12Nuuk 19 CTD004 9Nuuk 19 CTD004 24Nuuk 24 CTD008 24-1Nuuk 24 CTD008 24Nuuk 26 CTD010 18Nuuk 26 CTD010 20Nuuk 27 CTD011 18,16,2Nuuk 28 CTD012 24,20Nuuk 28 CTD012 22,18Nuuk 29 CTD013 22,18Nuuk 29 CTD013 24,20Nuuk 33 CTD014 12,18,4Nuuk 33 CTD014 24,20,18,12Nuuk 33 CTD014 22,20Nuuk 33 CTD014 20,14,8,6Nuuk 33 CTD014 4Nuuk 39 CTD015 24,22,20,19,18Nuuk 40 CTD016 24,20S.Greenland 46 CTD018 22,17S.Greenland 46 CTD018 24,20S.Greenland 54 CTD020 24,23,22,21S.Greenland 56 CTD022 24,22,20,18S.Greenland 59 CTD024 24,22,20,18
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DY081CRUISEREPORT
Samplingprotocolsforcomplementarystudies
Nitrogenisotopes
Nitrogenisotopes(denotedbyd15N)provideinformationaboutnitrogencyclinginseawater,acomplementarysystemtothesiliconcycle.Thesamplesweretakenwhilstwearingvinylglovesonly,andtakeninduplicate.ThebottleswererinsedthreetimeswithseawaterfromtheNiksin,filteredusingeitheranAcropakorinlinefilter(0.2µm).Headspaceisleft,andthesampleisflashfrozenat-80˚C,thenfrozenat-20˚C.ThesampleswillbewillbeanalysedbyDrSianHenleyattheUniversityofEdinburgh.
Silicon-32incubationexperiments
Incubationswithradioactivesilicon-32werecarriedout(Table20)toquantifythedegreeofkineticlimitationofSiuptakebyambientsilicicacidtodeterminewhethersilicicacidlimitationlimitstheproductionofdiatomsilica,andpotentially,diatomgrowth.TheresultsfromDY081willbecompliedandcomparedtoresultsfromsimilarexperimentsfromtheKrauseLaboratoryintheBeringSea(June2017)andcoastalGreenland(April–June2017).
TABLE20:SILICON-32SAMPLINGEVENTSDURINGCRUISEDY081.
ICY-LABStation SamplesCollected 32SiDepths
Sampled
A,E,orK Incubation
Time
DY081_001_CTD001
Full12DepthProfile 5SurfaceDepths Ambient&Enhanced
24hours
DY081_012_CTD002
Full12DepthProfile+Kinetic
4SurfaceDepths Ambient&Enhanced
24hours
DY081_012_CTD002
Full12DepthProfile+Kinetic
20.9 Kinetic 12hours
DY081_017_CTD03
KineticfromAUVCalibration
7.7 Kinetic 12hours
DY081_019_CTD04
Full12DepthProfile+Kinetic
4SurfaceDepths Ambient&Enhanced
24hours
DY081_019_CTD04
Full12DepthProfile+Kinetic
17.2 Kinetic 12hours
DY081_022_CTD06
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_023_CTD07
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_024_CTD08
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_025_CTD09
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_026_CTD10
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_027_CTD11
Full8DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_029_CTD13
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_033_CTD14
Full12DepthProfile+Kinetic
14.9 Kinetic 12hours
DY081_033_CTD14
Full12DepthProfile+Kinetic
10TopDepths Ambient&Enhanced
24hours
DY081_039_CTD15
Full13DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
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DY081CRUISEREPORT
DY081_040_CTD16
Full13DepthProfile 5SurfaceDepths Ambient&Enhanced
24hours
DY081_043_CTD17
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24hours
DY081_046_CTD18
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24Hours
DY081_054_CTD20
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24Hours
DY081_055_CTD21
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24Hours
DY081_056_CTD22
Full12DepthProfile 4SurfaceDepths Ambient&Enhanced
24Hours
DY081_059_CTD24
Full12DepthProfile 5SurfaceDepths Ambient&Enhanced
24Hours
AteachCTDlocation,surfacewatersinorjustbelowthephoticzonewerecollectedfor32Siincubations.Thesampleswerespikedwiththeradionuclideandallowedtoincubateinambientwaterconditions(temperature,lightsaturation)fora24-hourlightcycle.Replicatesateachdepthweregiven20µMsilicateenhancementsforcomparisonagainstambientwatersamples.Followingincubations,thesampleswerefilteredthrougha1.2µm25mmpolycarbonatefilteranddriedforfurtheranalysisfollowingthecruise.Duringthecruise,wecompletedtwenty24-hourincubationsandfive12-hourkineticincubations,finishingthecruisewithatotalof202samples.UponreturningtotheDauphinIslandSeaLab,sampleswillbeallowedtositfor5-monthstoestablishsecularequilibriumwith32PandanalyzedonaBetacountertodetermineSiuptake.
Radiumisotopes
Radium(Ra)isproducedcontinuouslyfromlithogenicmaterialbythedecayofthorium(Th)andthusdisplayselevatedconcentrationsnearanysediment-waterinterface.Thus,Racanbeusedtoinvestigatethefateofsolutessourcedfrombenthicsedimentsorglacialmeltwater.Radiumispresentintheoceanasfournaturally-occurringradioactiveisotopes:223Ra,224Ra,226Raand228Ra,withhalf-lives(11.4d,3.66d,1600yand5.75y,respectively)spanningarangeoftimescalesrelevanttobothverticalfluxesof(micro)nutrientsoutofsedimentsintotheoverlyingwatercolumn,aswellashorizontaladvection.AsRaisnotparticlereactive,thedecreaseinconcentrationofeachshort-livedisotopeawayfromthesource(sediments)canbeusedtotracepathwaysofadvectionaswellasconstraintimescalesoftransport.Theprimaryobjectiveoftheradium(Ra)workdonewithICY-LABistoinvestigatethefateoftracemetalsfromGreenlandglacialmeltwaterwhenthiswaterenterstheLabradorSea.Rameasurements,tracemetalsandoxygenisotopeswillbecombinedtoinvestigatethemagnitudeofanyFesupplyintheNuukregionandalongthecoastofsouthwestGreenland(AnnettNERCFellowship).
Rasamplingrequiresverylargevolumesofwater,asRaactivitiesaretypicallyverylowawayfromsedimentsources.Samplesof~200LwerecollectedfromthetracemetalcleanTowfish.TheTowfishwasdeployedfromtheaftportcrane,toadepthof~5m(depthwhenstationary).Thepumpwasruncontinuouslywhilethefishwasunderwater,towingatspeedupto10knots.Whennecessary,thefishwasbroughtupto1mforCTDops,orrecoveredontodeckforROVwork.
Sampleswerecollectedwhileunderwayorstationary(Table21),andstoredin20Lcollapsibleplasticcontainers.Each20Lwatersamplewasweighedusingabeamscale,andstoredonshelvesinthehangarspace.Additionalsampleswerealsocollectedfromthestainless-steelSea-BirdCTDsystem,Niskinbottleonthemegacoreframe,andcore-topwaterfrommegacores.Thesesampleswerecollectedinto20LbottlesasforTowfishwater.
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DY081CRUISEREPORT
Thesampleswerethenpassedthroughacolumnholding20gofMnO2-coatedacrylicfiber,whichstronglybindsRa.ThefiberswerethenrinsedwithMilli-QandloadedintoaRaDelayedCoincidenceCounter(RaDeCC;ScientificComputerInstruments,USA)systempurgedwithHegas,anddecayofRawascountedfor6-10htoquantify223Raand224Racontent.Followingdecayoftheseshort-livedisotopes,thefiberswillbere-analysedusingtheRaDeCCtodeterminetheactivityoftheparentisotopes(227Acand228Th).
Fortowfishsamples,asubsamplewascollectedintoacid-clean250mLLDPEbottlesforanalysisofthelong-lived226Raisotopesbymassspectrometryforcalibration.
Atotalof43sampleswerecollectedforRaisotopes,fromallthreemainsitesaswellastheNuuktosouthwestGreenlandtransit.Ofthese,25weresurfacesamplescollectedfromthetowfishprovidingagoodspatialcoveragetoinvestigatemeltwaterderivedRadistribution.ElevensampleswerelargevolumespooledfromNiskinbottlesontheCTDrosette,2werenear-bottomsamplescollectedfromtheNiskinbottleonthemegacoreframe,and4coretopwatersampleswerecollectedfromthemegacores,givingadditionalinformationonbenthicfluxesateachofthethreesites.
TABLE21:RADIUMSAMPLINGEVENTSDURINGCRUISEDY081.
DY081 Radiumsamplelist
Location Date Station Gear Event Vol(L)1 OK 07/08/17 3 MGA01 1 2.52 OK 07/08/17 3 MGA01 9 0.983 OK 07/10/17 6 FSH01 2 199.344 OK 07/12/17 12 CTD02 1-9 90.225 Nuuk 17/7/17 17 CTD03 1-10 103.276 Nuuk 17/7/17 17 CTD03 11-22 1257 Nuuk1.1 17/7/17 14 FSH02 14 230.258 Nuuk1.2 18/7/17 14 FSH02 17 211.189 Nuuk1.3 18/7/17 14 FSH02 19 209.3410 Nuuk1.4 18/7/17 14 FSH02 21 200.3811 Nuuk1.4 18/7/17 23 CTD07 11-20 72.7512 Nuuk3.1 19/7/17 14 FSH02 22 205.9413 Nuuk3.2 19/7/17 14 FSH02 25 209.5414 Nuuk3.3 19/7/17 14 FSH02 27 199.3315 Nuuk2.3 19/7/17 14 FSH02 29 215.516 Nuuk2.3 19/7/17 27 CTD11 7-14 82.9717 Nuuk2.2 19/7/17 14 FSH02 31 203.9818 Nuuk2.1 19/7/17 14 FSH02 33 211.7519 Nuuk1.5 21/7/17 32 FSH03 2 144.2820 Nuuk1.5 21/7/17 32 FSH03 2 116.521 Nuuk
CTD1523/7/17 38 FSH04 3 184.92
22 NuukCTD16
24/7/17 38 FSH04 5 164.88
23 NuukCTD16(2)
24/7/17 38 FSH04 9.5 183.98
24 NuukCore 24/07/17 42 MGA04 6 0.9625 SWG-400 25/07/17 38 FSH04 11 215.92
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DY081CRUISEREPORT
26 SWG-300 25/07/17 38 FSH04 14 211.927 SWG-200 25/07/17 38 FSH04 17 206.5628 SWG-100 25/07/17 38 FSH04 20.5 214.929 SWG1 25/07/17 38 FSH04 25 206.6930 SWG2 26/07/17 45 FSH05 2 206.7231 SWG2 27/07/17 47 CTD19 1-8 81.9332 SWG2 27/07/17 47 CTD19 9-16 83.3533 SWG2 27/07/17 47 CTD19 17-24 82.4134 SWG2 27/07/17 49 MGA05 xx 1.6335 SWG3 29/07/17 53 FSH06 2 208.17536 SWG3 30/07/17 53 FSH06 11 213.5837 SWG3 30/07/17 53 FSH06 16 212.6338 SWG3 31/07/17 58 CTD23 1 82.1539 SWG3 31/07/17 58 CTD23 9 81.74540 SWG3 31/07/17 58 CTD23 17 82.65541 SWG3 30/07/17 57 MGA07 1 9.4642 SWG3 30/07/17 57 MGA07 1 10.0543 SWG3 30/07/17 57 MG07 9 9.12 Total: 5991.315
Tracemetalsandtracemetalisotopes
Tracemetalsampleswerecollectedfromthetrace-metalcleantowfishsystemwhentheshipwasmovingat>0.5kts.Thewaterflowwasdirectedintothecleanlab,andleftrunningfor~1minutetoflushthetubing.A0.2µmacropakcartridgefilterwasattachedandflushedwithatleast0.5Lofseawater.Dissolvedtracemetal(dTM)sampleswerethencollectedintoacid-washed250mLHDPEbottles,andacid-washed4Lbottlesfortracemetalisotopeanalysis.Filteredwaterwasalsocollectedfornutrientanalysis.Unfilteredwaterwascollectedinto125mLacid-washed125mLHDPEbottlesfortotaldissolvabletracemetal(TdTM)analysis,anda4Lsamplewascollectedforparticulatetracemetals(pTM).Samplesforoxygenisotopes(d18O)werealsocollectedfromtheunfilteredtowfishwater.Allsamplingandhandlingwasperformedfollowingcleanlabprotocols,wearingtyveklabcoats,hairnets,andclass-100particle-freegloves.Nutrientsampleswerefrozenat-20˚C,andwillbeanalysedatthePlymouthMarineLaboratory,UK.SamplesfordTMandTdTMwereacidifiedwith1mLL-1ultrapurehydrochloricacidandstoredatroomtemperatureinthedark.
SamplesforpTMswereimmediatelyfilteredonto25mmSuporfilters,0.45µmporesize.Filterswereattachedtoadaptorsonthe4Lbottles,andpressurefilteredat<5PSIfor2-3hoursoruntilthebottlewasempty.Filtersweregentlydriedusingacleansyringeforsuction,andbydabbingthefilteronanacid-cleanblotterfilter.pTMsampleswerestoredfrozenat-20˚C.Allfiltermanipulationswereperformedinalaminarflowhoodwithacidwashedequipment.dTM,TdTMandpTMsampleswillbeanalysedattheSherrellLabatRutgersUniversityinNewJersey,USA.
Atotalof83samplingeventswereundertakenfortracemetals(Table22).Allthreemainsamplinglocationswerecovered,includingthefullCTDgridatNuuk.SampleswerealsocollectedduringthetransitsfromOrphanKnolltoNuuk,NuuktosouthwestGreenland,andsouthwestGreenlandtoErikDrift.Additionallarge-volumesampleswerealsocollectedfromthefiltered,cleanseawatersupplyforprojectpartnersfromselectedsites,e.g.fortracemetalisotopeanalysis(DrSusanLittleatImperialCollegeLondon),andneodymiumisotopeanalysis(forProfKevinBurton,UniversityofDurham).
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DY081CRUISEREPORT
TABLE22:TRACEMETALSAMPLINGEVENTSDURINGCRUISEDY081.
Stn Gear Evnt Date dTm TdTM pTM TM-
isos
Nd
isos
d18O d30Si Nuts
1 3 FSH01 1 07/09/17 � � � 2 3 FSH01 3 07/10/17 � 3 14 FSH02 2 13/07/17 � 4 14 FSH02 3 14/07/17 � 5 14 FSH02 4 14/07/17 � �6 14 FSH02 5 14/07/17 � �7 14 FSH02 6 15/07/17 � 8 14 FSH02 7 15/07/17 � � � �9 14 FSH02 8 16/7/17 � �10 14 FSH02 9 16/7/17 � �11 14 FSH02 10 16/7/17 � �12 14 FSH02 11 17/7/17 � � � �13 14 FSH02 12 17/7/17 � �14 14 FSH02 13 17/7/17 � � � � 15 14 FSH02 15 18/7/17 � � 16 14 FSH02 16 18/7/17 � � � � 17 14 FSH02 18 18/7/17 � � � 18 14 FSH02 20 18/7/17 � � � � 19 14 FSH02 21.5 18/7/17 � � 20 14 FSH02 23 19/7/17 � � � 21 14 FSH02 24 19/07/17 � � � � 22 14 FSH02 26 19/7/17 � � � � 23 14 FSH02 28 19/7/17 � � � � 24 14 FSH02 30 19/7/17 � � � � 25 14 FSH02 32 19/7/17 � � � � 26 32 FSH03 1 21/07/17 � � � � 27 38 FSH04 1 23/07/17 � �28 38 FSH04 2 23/07/17 � � � 29 38 FSH04 4 24/07/17 � � � � 30 38 FSH04 6 24/07/17 � 31 38 FSH04 7 24/07/17 � �32 38 FSH04 8 24/07/17 � �33 38 FSH04 9 24/07/17 � � �34 38 FSH04 10 25/07/17 � � � �35 38 FSH04 12 25/07/17 � � � � �36 38 FSH04 13 25/07/17 � � � � �37 38 FSH04 15 25/07/17 � � � � � �38 38 FSH04 16 25/07/17 � � � � �39 38 FSH04 18 25/07/17 � � � � �40 38 FSH04 19 25/07/17 � � �
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DY081CRUISEREPORT
41 38 FSH04 20 25/07/17 � � � � � �42 38 FSH04 21 25/07/17 � � � � � �43 38 FSH04 22 26/07/17 � � � � � �44 38 FSH04 23 26/07/17 � � � � 45 38 FSH04 24 26/07/17 � 46 38 FSH04 26 26/07/17 � � �47 38 FSH04 27 26/07/17 � �48 45 FSH05 1 26/07/17 � � � �49 45 FSH05 3 27/07/17 � � � � �50 45 FSH05 4 27/07/17 � 51 45 FSH05 5 27/07/17 � � 52 45 FSH05 6 27/07/17 � �53 45 FSH05 7 27/07/17 � � � �54 45 FSH05 8 27/07/17 � �55 45 FSH05 9 27/07/17 � �56 45 FSH05 10 27/07/17 � �57 45 FSH05 11 27/07/17 � � �58 45 FSH05 12 27/07/17 � �59 45 FSH05 13 27/07/17 � �60 45 FSH05 14 27/07/17 � � � �61 45 FSH05 15 27/07/17 � � �62 45 FSH05 16 27/07/17 � � � �63 45 FSH05 17 27/07/17 � � � �64 53 FSH06 1 29/07/17 � � � 65 53 FSH06 3 30/07/17 � � 66 53 FSH06 4 30/07/17 � � � �67 53 FSH06 5 30/07/17 � � � �68 53 FSH06 6 30/07/17 � � � �69 53 FSH06 7 30/07/17 � � � �70 53 FSH06 8 30/07/17 � � � �71 53 FSH06 9 30/07/17 � � � �72 53 FSH06 10 30/07/17 � � � 73 53 FSH06 12 30/07/17 � � � 74 53 FSH06 13 30/07/17 � � � � �75 53 FSH06 14 30/07/17 � � � � � �76 53 FSH06 15 30/07/17 � � 77 53 FSH06 17 31/07/17 � � 78 53 FSH06 18 31/07/17 � � �79 53 FSH06 19 31/07/17 � � � �80 53 FSH06 20 31/07/17 � � � �81 53 FSH06 21 31/07/17 � � � �82 53 FSH06 22 31/07/17 � � � �83 53 FSH06 23 31/07/17 � � � �
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DY081CRUISEREPORT
Neodymiumisotopes(radiogenic)
Neodymiumisotopes(radiogenicandstable)inseawaterreflectweatheringandseafloorexchangeprocesses,andhavebeensampledfor,tohelpconstraininputsofmaterialfromterrestrialandmarineweathering.SamplesforradiogenicNdisotopeswerecollectedforProfTinavanderFlierdt(ImperialCollege);samplesforstableNdisotopeswerecollectedforProfKevinBurton(UniversityofDurham).
Filter10litresofwaterthrough0.2µmAcropakfilterorinlinefilterandacidifiedto0.1%v/vhydrochloricacid(RomilUpA).StoredincoolstowforanalysisintheUK.
Neodymiumisotopes(stable)
Filter10litresofwaterthrough0.45µmAcropakfilterorinlinefilter.StoredincoolstowforanalysisintheUK.SomesamplesalsotakenbyTowfish(seeabove).
Porefluidsamplingandcoreincubations
OneofthekeyaimsofICY-LABistoinvestigatetheinteractionbetweenseawaterandsedimentsinglacialregions.Tothisend,wecollectedporefluidsamplestobepairedwithsedimentandoverlyingseawatersamples,andwecarriedoutcoreincubationexperiments.
Porefluids
Rhizonfilters(Rhizosphere®)wereusedtofilterporefluidsfrombothmegacoreandpushcoretubes(Figure46).Approximatelyhalfofthesolutionswerestoredundercoolconditions,andtheremainderwasfrozenat-20˚C.Someoftheporefluidsweremeasuredfordissolvedsiliconontheship(theremainderwillbecarriedoutonshore).PorefluidsiliconisotopeanalysiswillbecarriedoutattheUniversityofBristol(followingunpublishedmethodsfromLucieCassarinoandDrKatharineHendry).Thefrozensampleswillbeanalysedforremainingnutrients,andfornitrogenisotopesbyDrSianHenley.
FIGURE46:POREFLUIDSAMPLINGOFAPUSHCORE.PHOTOBYA.JACOBEL.
Inaddition,whenmaterialwasavailable,twomegacoresweresectionedat2-5cmintervalsandfrozenforProfTinavanderFlierdt,ImperialCollege.
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DY081CRUISEREPORT
Coreincubations
Coreincubationswereusedtoassessthesupplyofdissolvednutrientsfromsedimentsandporefluidsintooverlyingseawaterviadiffusionovertime.
Onemegacoretubeperrecoverywasfittedwithatightlowerseal,andanuppersealwithasamplingdeviceandmagneticstirrerattachedwhilstondeck(Figure47).Initially,smallamountsofairwereremovedfromtheoverlyingspace(sothatonlyoverlyingseawaterremained)andasamplewastaken.Thecorewasleftundercontrolledtemperatureandlightconditionsandsampledevertwohoursforatleast24hours.Thesampleswerefiltered;84pprox..25-30mLwasstoredundercoolconditions,and25-30mLwasfrozenat-20˚C.
85
DY081CRUISEREPORT
FIGURE47:COREINCUBATIONDESIGN(BASEANDTOPPLUGS,OVERTHEPAGE)ANDIMPLEMENTATION(ABOVE)DURING
DY081.
TABLE23:POREFLUIDANDCOREINCUBATIONSAMPLESFROMDY081.OK=ORPHANKNOLL;
SG=SOUTHERNGREENLAND.
Station Gear Event Site Depth(m) Lat Long Purpose #Samples
003 MGA001 002 OK 3721 50.16 -45.51 Incubation 26
003 MGA001 004 OK 3721 50.16 -45.51 PoreFluids 1
003 MGA001 007 OK 3721 50.16 -45.51 PoreFluids 1
003 MGA001 009 OK 3721 50.16 -45.51 PoreFluids 34
008 ROV329 020 OK 1745 50.55 -46.19 PoreFluids 9
008 ROV329 040 OK 1682 50.56 -46.19 PoreFluids 9
008 ROV329 053 OK 1711 50.57 -46.18 PoreFluids 3
009 MGA002 002 OK 1770 50.52 -46.28 Incubation 245
009 MGA002 003 OK 1770 50.52 -46.28 PoreFluids 13
018 MGA003 001 Nuuk 1301 63.82 -53.77 PoreFluids 32
018 MGA003 002 Nuuk 1301 63.82 -53.77 Incubation 20
034 ROV334 001 Nuuk 940 63.87 -53.29 PoreFluids 12
034 ROV334 007 Nuuk 683 63.86 -53.28 PoreFluids 12
035 ROV335 074 Nuuk 845 63.33 -52.75 PoreFluids 10
035 ROV335 003 Nuuk 1326 63.33 -52.78 PoreFluids 8
035 ROV335 042 Nuuk 1002 63.32 -52.77 PoreFluids 0
035 ROV335 002 Nuuk 1326 63.33 -52.78 PoreFluids 4
035 ROV335 041 Nuuk 1002 63.33 -52.77 PoreFluids 11
035 ROV335 073 Nuuk 845 63.33 -52.75 PoreFluids 2
037 ROV336 043 Nuuk 381 63.61 -52.90 PoreFluids 15
037 ROV336 034 Nuuk 499 63.60 -52.91 PoreFluids 16
037 ROV336 005 Nuuk 549 63.60 -52.92 PoreFluids 19
037 ROV336 035 Nuuk 497 63.60 -52.91 PoreFluids 16
037 ROV336 006 Nuuk 569 63.60 -52.92 PoreFluids 16
86
DY081CRUISEREPORT
037 ROV336 045 Nuuk 349 63.61 -52.90 PoreFluids 7
42 MGA004 002 Nuuk 519 63.55 -52.23 PoreFluids 18
42 MGA004 003 Nuuk 519 63.55 -52.23 Incubation 24
049 MGA005 002 SG 573 60.26 -46.89 Incubation 24
059 MGA005 003 SG 573 60.26 -46.89 PoreFluids 29
050 ROV338 004 SG 742 60.09 -46.63 PoreFluids 16
050 ROV338 005 SG 742 60.09 -46.63 PoreFluids 12
050 ROV338 023 SG 957 60.09 -46.64 PoreFluids 8
050 ROV338 058 SG 983 60.08 -46.64 PoreFluids 12
050 ROV338 059 SG 983 60.08 -46.64 PoreFluids 24
051 MGA006 002 SG 1326 60.12 -46.66 PoreFluids 30
051 MGA006 003 SG 1326 60.12 -46.66 Incubation 24
052 ROV339 003 SG 1085 59.93 -46.50 PoreFluids 19
052 ROV339 038 SG 807 59.93 -46.50 PoreFluids 17
052 ROV339 040 SG 532 59.94 -46.51 PoreFluids 18
052 ROV339 004 SG 1085 59.93 -46.50 PoreFluids 21
052 ROV339 037 SG 807 59.93 -46.50 PoreFluids 21
052 ROV339 041 SG 532 59.94 -46.51 PoreFluids 8
052 MGA007 002 SG 2149 59.46 -44.42 Incubation 24
052 MGA007 003 SG 2149 59.46 -44.42 PoreFluids 12
Shipboardwateranalyses
SalinitySalinitywasmeasuredonboardbyNMFtechniciansaccordingtostandardprotocolusinganGuildlineAutosalsalinometerandsoftware,cross-checkedwithIAPSOstandards(seeNMFtechnicalreportformoredetails).AtthewestGreenlandsites,allNiskinsthatweresampledforoxygenisotopeswerealsosampledforsalinity,tocarryoutfreshwaterbudgetcalculations(e.g.Hendryetal.,2011).Atothersites,only3-4Niskinsweresampledforsalinity,tocarryoutasensorcalibration.
DissolvedsiliconDissolvedsiliconwasmeasuredinsomeporefluidprofilesusingHachLtdreagentsforultra-lowrangeSiO2detection.MeasurementswerecarriedoutonaV-1200Visspectrophotometer,andsampleswerecalibratedagainstaten-pointstandardcurve.
Themeasurementprotocolisasfollows:
• Fourteendropsofmolybdatesolutionareaddedtoblank,standardsandsamplesandleftforfourminutes.
• Citricacidpowder(1sachet)isaddedtoeachblank,standardandsampleandleftforoneminute.• Aminoacidcatalyst(1sachet)isaddedtoeachstandardandsample(notblank)andleftfortwominutes.• Thesolutionsaremeasuredat810nm,blank-correctedandstandardised.
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DY081CRUISEREPORT
DissolvedoxygenDissolvedoxygenmeasurementswereattempted,tocalibratetheoxygensensorontheCTD.However,duetotitratorfailure,themeasurementswereabandoned.Instead,theoxygensensorswillbecalibratedpost-cruise.
Forreference,themeasurementprotocolisasfollows:
Startup
• Moveburettetiptotheelectrodeholder.• Flushtheburettetipwithfreshthiosulphate.
o Menu>OK>Manualcontrol>OK>PREP>OK.o Thisflushes10mLthroughtheburette,2cyclesbythepiston,goodifnotusedrecently.o DOS>OK>Start(holddown)tomanuallydispensedesiredamount.o PressBacktoreturntomainmenu.o RinseexcessthiosulphatefromtheburettetipwithMQ.
• SelectDissolvedO2method.o Method>OK>DissolvedO2>OK.
• Moveelectrodetoelectrodeholder.• RinsetheelectrodewithMQ,ifabigdropofMQishangingofftheelectrodebulbremoveitgentlywithakimwipe.• Dispense1-2mLofH2SO4togetfreshacidinthepipettetip.Runningsamples• Selectnextsample.• Removewatersealwithpipetteandcompletelydryaroundthestopperwithakimwipe.• Removestopperbytwistingandgentlypulling.Avoid“chinking”thestopperasthiscanchipthestopperandrenderthebottlecalibrationincorrect.Ifyoucannotremovethestopperdonotforceit.• Add1mLofH2SO4tothesamplewiththepipettetipjustbelowthesamplesurface.Gentlytipthebottleandruntheaciddownthesideofthebottle.Thisistopreventtheintroductionofbubblesandtoavoiddisturbingtheprecipitate.• Usingthestirrerbarretriever,traceasmallstirrerbardowntheneckofthebottleandtothebottomofthebottle.Thisalsoistopreventtheintroductionofbubblesandtoavoiddisturbingtheprecipitate.• Placesampleonstirrerplate.• Lowertheelectrodeandburettetipintothesample.• OntheTitrino.
o Ensurethe“DissolvedO2”methodisselected.Ifnotrefertothestartupsection.o Press“Start”o EntertheshortIDinID1.ID1>OK>WXXXX>Accept>OK.Thekeypadcanbeusedtoenternumbers(NumLockmustbeon)butnotletters,andBS=backspace.o EnterthebottlenumberinID2.ID2>OK>XX>Accept>OK.o Ignoretheunitline.o Press“Start”tobeginthetitration.
• Thetitrationwilltakeabout60sec.• WritedownthetitervolumeontheDissolvedO2logsheet.• Raisetheelectrodeandburettetiphighenoughsoasnottocatchthebottleontheelectrodebulb.• Removethesample.• RinsetheelectrodeandburettetipwithMQ,ifabigdropofMQishangingofftheelectrodebulbremoveitgentlywithakimwipe
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DY081CRUISEREPORT
• Retrievethestirrerbarfromthesample,drythestirrerbar,capthebottle,returntotheboxandselectthenextsample.
ChlorophyllpigmentsAtrichromaticmethod(Mackerethetal.,1978)wasusedtodeterminechlorophyll-a,bandcspectrophotometricallyinthenearsurfaceseawatersamples(exceptCTD01).Thesampleswerepassedthrougha25mmGFFfiltersandfrozenuntilextraction.Extractionwascarriedoutusingaqueousacetoneandmagnesiumcarbonate,inordertopreventaciditythatcoulddamagethepigments.Oncelefttosteepfor24hoursinthedarkat4˚C,thesampleswerecentrifugedandanalysedat750nm(tocorrectforturbidity),664,647and630nmonaV-1200Visspectrophotometer.Absorbancevalueswerethenusedinequations1to3tocalculatetheconcentrationofchlorophyll-a,bandcpervolumeoffilteredsample(Eq.4).
Chlorophyll a (mg/L) = 11.85*(OD664) – 1.54*(OD647) – 0.08*(OD630) (1)
Chlorophyll b (mg/L) = 21.03*(OD647) – 5.43*(OD664) – 2.66*(OD630) (2)
Chlorophyll c (mg/L) = 24.52*(OD630) – 7.60*(OD647) – 1.67*(OD664) (3)
Chlorophyll x, mg/m3 = (Chl x) * extract volume, L/ Volume of sample, m3 (4)
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DY081CRUISEREPORT
Chapter8:StandAlonePumps
Introduction
WecollectedwatercolumnmaterialusingStandAlonePumps(SAPs)forbiogenicsilica,major/minorelements,andorganicmatter,toquantifytheparticulatesreleasedinfreshwatersfromWestGreenlandandtocomparethemtoparticulatesfromanopenoceancomparisonsite(OrphanKnoll).
SummaryofSAPSevents
TABLE24:TABLEOFSAPSSAMPLINGEVENTSDURINGCRUISEDY081(OVERTHEPAGE).
SamplingprotocolNylonpre-filtermesheswereacidcleanedandGFFfilterswereashedpriortothecruise,andwrappedinashedfoil.GFFandSuporfilterswerecleanlyfittedintothecleanedpancakefilters(oneperfilter)andattachedtotheSAPS.
TheSAPSweredeployed(seeChapter5)andpumpedfor1.5hours.Whenretrieved,totalvolumepumpedisrecordedandthepancakefiltersremovedandallowedtodrainundercoolconditions.GFFfilterswereremovedcleanlyinafumehoodandsplitintwo,labelledandphotographed,foldedintwoandwrappedinpre-ashed,cleanfoil,andflashfrozendirectlyat-80˚Candthenstoredat-20˚C.TheSuporfilterswereremovedcleanlyinalaminarflowhood,dividedintothreepieces,whicharephotographedandlabelled,foldedinhalfandplacedinacleanbag,andflashfrozenat-80andmovedto-20forstorage.Nylonmeshfilterswerefrozenforstorage,oracidwashedandreused.Blanksweretakenbyinstallingandremovingbothtypesoffiltersintothepancakehousingsundertheconditionsinthelaboratory.
Site StationNo
GearNo JDay(Start)
Depth(m)
Filtertype
Pumptime(mins)
Pumpingvol(L)
ID Comments
OrphanKnoll 2 SAP001 188 2400 GFF 90 1212 CHLOE
OrphanKnoll 2 SAP001 188 2400 Supor 47? 338 SANDIE
OrphanKnoll 2 SAP001 188 200 GFF 90 1170 POLLY
OrphanKnoll 2 SAP001 188 200 Supor 90? 604 MINNIE Smallerpumpingvolumemaybepartlyduetoshorterbatterylife
Nuuk 20 SAP002 199 630 GFF 90 1074 CHLOE
Nuuk 20 SAP002 199 630 Supor 90 679 SANDIE
Nuuk 20 SAP002 199 100 GFF 90 1015 POLLY
Nuuk 20 SAP002 199 100 Supor 90 8 MINNIE Filterhousingwasfullofwaterthatwasreluctanttodrainwhenopened
Nuuk 35 SAP003 202 450 GFF 90 1228 CHLOE
Nuuk 35 SAP003 202 450 Supor 90 723 SANDIE
Nuuk 35 SAP003 202 250 GFF 90 14 MINNIE MINNIEstillpumpingsmallvolume,latertofindfaultypumpparts
Nuuk 35 SAP003 202 250 Supor 90 593 POLLY
Nuuk 41 SAP004 205 400 GFF 90 1139 CHLOE
Nuuk 41 SAP004 205 165 Supor 90 557 SANDIE Suporfilternotcutduringsampling
Nuuk 41 SAP004 205 100 GFF 90 238 MINNIE Spiralplateinstalledupsidedown
SGreen 48 SAP005 208 350 GFF 90 990 CHLOE
SGreen 48 SAP005 208 350 Supor 90 636 SANDIE
SGreen 48 SAP005 208 100 GFF 90 513 POLLY
SGreen 48 SAP005 208 100 Supor 90 816 MINNIE
SGreen 60 SAP006 212 500 GFF 90 13 CHLOE Filtertorn
SGreen 60 SAP006 212 500 Supor 90 723 SANDIE
SGreen 60 SAP006 212 150 Supor 90 673 POLLY
SGreen 60 SAP006 212 150 GFF 90 1110 MINNIE Smalltearinfilter
Table24
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DY081CRUISEREPORT
Chapter9:SedimentsamplingIntroduction
SedimentsamplingwascarriedoutonDY081,toassesstheroleofsediment-waterinteractionsinbiogeochemicalcyclingintheLabradorSea,andforcomplementarypalaeoceanographicandproxycalibrationprojects.Sediment-waterinteractionswerecharacterisedusingporefluidprofilingandcoreincubations.
CoringstrategyandsamplecollectionTheDY081sedimentcoringstrategywasdesignedtoobtaincoretopsedimentsandlongsedimentcoresfrommultiplelocationsateachofthethreemainstations:OrphanKnoll,NuukandSouthwestGreenland.Specifically,atOrphanKnollweselectedcoresiteslikelytobeinfluencedbyProto-NorthAtlanticDeepWaterandoutflowfromtheHudsonStraitasacomponentofLabradorSeaWaters(LSW).AtNuuk,wetargetedsedimentslocallyinfluencedbytheoutflowofshallowsubglacialmeltwaterandparticulates,inadditiontosedimentslocatedatthebottomofthecontinentalshelfandinfluencedbytheambientwatermasses.Finally,atSouthwestGreenlandoursamplingstrategywastargetedatobtainingsedimentsinfluencedbythesurficialflowoftheEastGreenlandCurrent(bringingcoldandfreshwaterfromtheArcticOcean),Iceland-ScotlandOverflowWater(ISOW)andrecirculatedLSW.
SampleCollection
SedimentsamplestofulfillDY081objectiveswerecollectedusingthreedifferenttechniqueswhichwereappliedateachofthestudysitesaccordingtothespecificsiteobjectives.WherepossiblesedimentsweresampledsuchthatundisturbedcoretopsamplescanbematchedwithNiskin,CTD,andSAPSdataandwatersamples.Ideally,sedimentandporewaterdatacanbepairedwithdatafromtheoverlyingwatercolumntoprovideinsightsintoprocessesoccurringatthesediment-waterinterface.Undisturbedcoretopsampleswerecapturedusingbothan8roundmegacorerigandpushcorestakenusingtheROVIsis’sarms.
AtOrphanKnollandSouthwestGreenlandanadditionalobjectivewastoobtainlong,continuoussedimentcoresthatwillbeusefulforpaleoceanographicreconstructions.Long-coresamplingwasperformedusingagravitycorerig.Afterrecovery,sedimentcapturedbythegravitycorebarrelwereextrudedandcutinto1.5msectionsfollowingstandardprotocol.
Sedimentsamplesandsubsampleswerenamedfollowingtheconventionsoutlinedelsewhereinthisreport.GearidentifiersareMGA,PSHandGVYformegacores,pushcoresandgravitycoresrespectively.Sub-samplesarelabeledwiththecruisename,stationnumber,gearnameandnumber,eventnumberandsedimentinterval.Anexampleofacompleteidentifierforthefirstgravitycoreofthecruisewouldbeasfollows:DY081_004_GVY001_EV01_0-1cm.
MegacoringSedimentssuccessfullyretrievedusingthemegacorewereslicedandpreservedinplasticbagsforfuturesamplingandstudy.Thesamplingresolutionwasdeterminedonthebasisofthedesignatedrecipientandplanneduseofthesediment.SuccessfulMCHtubesdesignatedforporefluidsamplingwerefirstrelievedofcoretopwaterandthensubsequentlyRhizonswereinsertedevery2cmdowncoretoextracttheporefluids.Toincreasetheefficacy
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ofporefluidremoval,50mLsyringeswereattachedtotheRhizonsandavacuumwascreatedinsidethesyringesbylockingthem‘open’usingwoodenblocks4.
EachofthemegacoresdeployedonDY081hadonetubeofmudselectedforcoreincubation.Additionalinformationaboutcoreincubationscanbefoundinthewatersamplingchapterofthisreport.
Inadditiontocapturingsediment,themegacorerigalsodeployeda10-LNiskinbottletocapturewatersamplesfromjustabovetheseafloor.Detailsonthesub-samplingandanalysisofthiswatercanbefoundinthewatersamplingchapterofthisreport.
PushCoringToobtainalargernumberofcoretopsamples,theROVIsiswasoutfittedwithupto12cylinderstoretrievesmallsedimentcores(seeChapter5;Figure48).Toobtainthemaximumamountofcoretopmaterialatagivenlocation,thesepushcoreswereoftentakenintriplicate.Replicateswerealsocommonlytakeninlocationswherepushcoreswithporefluidholesweredeployed,retrievebothsedimentsforporefluidextractionandtraditionalanalyses.Dependingonthesuccessofretrieval-andwhetherornotporefluidswereobtainedfromthecores-pushcoresweresubsampledatupto1cmresolution.Allsamplesweresubsequentlystoredunderrefrigeratedconditions.
FIGURE48:PUSHCORINGFROMTHEROV.
GravityCoringGravitycoresweredeployedatOrphanKnollandSWGreenlandtoobtainlongsedimentsequencesforpaleoceanographicanalysis.Successfulcoreswerecutinto1.5msectionsandlabeledalphabeticallyinorderofextrusionfromthecorebarrel.Subsequentlycoresectionswerere-labeledsuchthatoldersedimentsareinsuccessivelyhighernumberedtubes.CoresectionsweresplitonboardusingaspeciallydesignedrouterandcradleprovidedbyVeitHuhnebachofNOC.Thecorelinerwasfirstroutedononesideandthenrotated180degreesandroutedasecondtime.Thecorewasthenliftedfromthecradleandamonofilamentlinewaspassedlengthwisebetweenthetwocutstoseparatethecoreintotwohalves.Oneofthehalveswasdesignatedtobethearchivehalfofthecoreandtheothertheworkinghalf.Bothsidesofthecorewerethencleaned/leveledusingglassslides,photographed,andthearchivehalfdescribed.Subsamplingwasthencarriedoutontheworkinghalf.
4Informationonmegacoreandpushcoreporefluidsampling,storageandanalysescanbefoundinthewatersamplingsections.
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SedimentRecovery
SiteSummaries CoringoperationsonDY081recovered5gravitycores,52megacorebarrelsand89pushcoresamplesforatotalofmorethan52mofsediment.ThebreakdownofsedimentretrievalbysiteandcoringtechniqueispresentedinTable25andFigure49.ROVpushcoresarenotdepictedinmapviewbecauseofthehighdensityofcorestakenateachofthethreelocations.Furtherdetailsaboutthedistributionofcoreswithinwatermassescanbefoundbelowinthesectionsoncorerecoveryateachsite.
TABLE25:SUMMARYOFCORINGSITESATEACHLOCATION.
FIGURE49:MAPSOFGRAVITYCORE(DOTS)ANDMEGACORE(DIAMONDS)LOCATIONSONABASEMAPOFPSS-78SALINITYAT50MWATERDEPTHFROMTHEGLODAPV2DATABASE.MAPSGENERATEDUSINGOCEANDATAVIEW.
SiteName Lat.Range(DDS)
Long.Range(DDS)
#GravityCores
GravityCoreSediment(m)
#Megacores
MegacoreSediment(m)
#Pushcores
PushcoreSediment(m)
OrphanKnoll
(50.05)-(50.57)
(-46.28)-(-45.10) 2 9.64 12 4.26 33 6.14
Nuuk (63.33)-(63.87)
(-53.77)-(-52.23) 0 0 16 6.05 34 5.46
SWGreenland
(58.61)-(60.26)
(-46.89)-(-43.58) 3 9.23 24 7.06 22 4.41
Totals 5 18.87 52 17.37 89 16.01
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OrphanKnollCoringoperationsatOrphanKnolltargetedsedimentbetween3,721and1,628mwaterdepth(Figure50).MGA002andGVY002at1,770mmayhavesampledsedimentsbathedbytheupperlimbofthedeepLabradorCurrentasindicatedbytheoxygenminimainthefigurebelow.ThebathyaldistributionofallsedimentcoresfromOrphanKnollarealsodepictedinthefigurebelow,illustratingthegoodcoretopcoverageprovidedbypushcoresamplesbetweendepthsof1,682and2656m.
FIGURE50:DEPTHDISTRIBUTIONOFSEDIMENTCORESFROMORPHANKNOLL.OVERLAYISLOCALCTDDATAREFLECTINGWATERTEMPERATURESANDDISSOLVEDOXYGENCONCENTRATIONS.
NuukCoringoperationsatNuuktargetedthesedimentsthatlayerthecontinentalshelfandslopebetween1,326and349mwaterdepth.Becauseofthestronggradientsintemperatureandsalinitythatresultfromthesite’sproximitytoconduitsforglacialmeltwater,samplingatNuuksiteswasmorespatiallydistributedthanatotherDY081siteswherewatermassesweretargetedbyvaryingthedepthofcoringefforts.ThespatialheterogeneityofwatermassesatNuukiswellillustratedinFigure51,whichdepictscoringlocationsinrelationtoCTDprofilesofwatertemperature.CoresatNuukincludesedimentsbathedbyboththeflowofambientwatersinthetroughsurroundingGreenlandaswellasthoseinfluencedbyfresh,coldwatersourcedfromglacialmelt.
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FIGURE51:BOTTOMBATHYMETRYOFNUUKSAMPLINGSITESWITHCTDTEMPERATUREPROFILESINRED,GREENTRIANGLES=MGA(EXCEPT04),BLUESQUARES=ROVPUSHCORESITES(SAMECOLOUR=SAMEDIVE).
SWGreenlandCoringoperationsatSWGreenlandsites(CapeFarewellandErikDrift)targetedsedimentbetween1,907and532mwaterdepth.AlthoughthedeepCTDprofiletakenat59.21˚N,-44.58˚Wdoesnotshoweasilyidentifiablewatermassstructureintemperaturespace(Figure52),thedissolvedoxygenmeasurementdoessuggestthatatleasttwodifferentwatermassesmaybathethecoredepthssampled.Wehypothesizethatbetween500and1,000mwatersarerepresentativeofrecirculatedLabradorSeawaterasitflowssouthwardsalongtheeasterncoastofGreenland.Below~1,500mwatersmayberepresentativeofagreaterproportionofIcelandScotlandOverflowWater(ISOW)anditispossiblethatthedeepestcoreat1,907mmaybeinfluencedbyamixtureofwatermassesthatincludeDenmarkStraitOverflowWaterandISOW.FurtheranalysisofDY081CTDdataandNiskinsampleswillbenecessarytoconfirmthesetentativewatermassdesignations.Ifourhypothesisprovescorrect,sedimentcoresfromSWGreenlandbeautifullycapturethedeep-watermassespresentatthesoutherntipofGreenland.
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FIGURE52:DEPTHDISTRIBUTIONOFSEDIMENTCORESFROMSOUTHWESTGREENLAND.OVERLAYISLOCALCTDDATAREFLECTINGWATERTEMPERATURESANDDISSOLVEDOXYGENCONCENTRATIONS.
ShipboardAnalyses
Uponretrievaleachsedimentcorewasenteredintothesedimentdatabaseanditslengthrecorded.Coreswerephotographedwiththeircruiseidentifierandarulerforscale.Subsequentlyadescriptionwasmadeofthecoretodenoteitsmajorcharacteristics.Featuresnotedincludedcolor,grainsize,mineralogy,foraminiferaabundance,sedimentarymatrix,cohesiveness,watercontent/porosity,smell,andthepresence,abundanceandsizeofanomalousclasts(oftenicerafteddebris).Coredescriptionsweredonebyhand,scannedandgroupedbyeventnumberforeaseofaccess.
SedimentSub-samplingSignificanteffortwasmadeonboardtosub-samplesedimentcoressothattheycouldeasilybedistributedtolabsforanalysis.Acompleteaccountingofthenatureofeachofthesesubsamplesisbeyondthescopeofthisreportbutisreadilyavailableonline.Asummaryofsubsamplestakencanbefoundinthetablesbelowwheretheyaregroupedbygeartypeinchronologicalorder.
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TABLE26:SUMMARYOFSUBSAMPLESFROMORPHANKNOLL.
Station Gear Event
WaterDepth(m)
Lat(DDS)
Long(DDS) Date
Maxlength(cm)
#Subsamples
003 MGA001 002 3721 50.16 -45.51 8/7/17 23.5 0003 MGA001 003 3721 50.16 -45.51 8/7/17 39.5 37003 MGA001 004 3721 50.16 -45.51 8/7/17 37.3 14003 MGA001 005 3721 50.16 -45.51 8/7/17 40.5 46003 MGA001 006 3721 50.16 -45.51 8/7/17 36.5 10003 MGA001 007 3721 50.16 -45.51 8/7/17 31.5 14003 MGA001 008 3721 50.16 -45.51 8/7/17 38.5 34003 MGA001 009 3721 50.16 -45.51 8/7/17 40 0004 GVY001 001 3721 50.16 -45.51 8/7/17 514 620005 ROV327 021 2344 50.05 -45.37 8/7/17 17 13005 ROV327 022 2348 50.05 -45.37 8/7/17 ? 1005 ROV327 023 2349 50.05 -45.37 8/7/17 19 19005 ROV327 047 2656 50.06 -45.36 9/7/17 13.5 7005 ROV327 048 2656 50.06 -45.36 9/7/17 17 13005 ROV327 049 2656 50.06 -45.36 9/7/17 25 20005 ROV327 054 2458 50.07 -45.35 9/7/17 27 26005 ROV327 055 2457 50.07 -45.35 9/7/17 21 21005 ROV327 056 2447 50.07 -45.35 9/7/17 22 22005 ROV327 067 2152 50.08 -45.36 9/7/17 18 13005 ROV327 068 2152 50.08 -45.36 9/7/17 18 9005 ROV327 069 2152 50.08 -45.36 9/7/17 20.5 22007 ROV328 004 1800 50.55 -46.19 10/7/17 18.5 15007 ROV328 005 1800 50.55 -46.19 10/7/17 29.5 24007 ROV328 021 1628 50.55 -46.20 10/7/17 19 14007 ROV328 022 1628 50.55 -46.20 10/7/17 13 1007 ROV328 023 1628 50.56 -46.20 10/7/17 24 1007 ROV328 024 1628 50.56 -46.20 10/7/17 17 1008 ROV329 020 1745 50.55 -46.19 11/7/17 24 1008 ROV329 021 1745 50.55 -46.19 11/7/17 11 11008 ROV329 040 1682 50.56 -46.19 11/7/17 24.5 1008 ROV329 041 1682 50.56 -46.19 11/7/17 27.5 27008 ROV329 052 1711 50.57 -46.18 11/7/17 19 19008 ROV329 053 1711 50.57 -46.18 11/7/17 26.5 1009 MGA002 002 1770 50.52 -46.28 11/7/17 38 0009 MGA002 003 1770 50.52 -46.28 11/7/17 28 1009 MGA002 004 1770 50.52 -46.28 11/7/17 35.5 40009 MGA002 005 1770 50.52 -46.28 11/7/17 37.5 40010 GVY002 001 1770 50.52 -46.28 11/7/17 450 535011 ROV330 001 1808 50.55 -46.19 12/7/17 17 17011 ROV330 002 1808 50.55 -46.19 12/7/17 10 2
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011 ROV330 003 1808 50.55 -46.19 12/7/17 15 4011 ROV330 004 1808 50.55 -46.19 12/7/17 16 16011 ROV330 005 1808 50.55 -46.19 12/7/17 8 2011 ROV330 006 1808 50.55 -46.19 12/7/17 5 1013 ROV331 001 1827 50.52 -45.10 12/7/17 27 24013 ROV331 002 1827 50.52 -45.10 12/7/17 27 23013 ROV331 003 1827 50.52 -45.10 12/7/17 18 4
TABLE27:SUMMARYOFSUBSAMPLESFROMNUUK.
Station Gear Event
WaterDepth(m)
Lat(DDS)
Long(DDS) Date
Maxlength(cm)
#Subsamples
018 MGA003 001 1301 63.82 -53.77 17/7/17 37 1018 MGA003 002 1301 63.82 -53.77 17/7/17 36.5 14018 MGA003 003 1301 63.82 -53.77 17/7/17 36 10018 MGA003 004 1301 63.82 -53.77 17/7/17 36 10018 MGA003 005 1301 63.82 -53.77 17/7/17 38 15018 MGA003 006 1301 63.82 -53.77 17/7/17 37 64018 MGA003 007 1301 63.82 -53.77 17/7/17 37 34018 MGA003 008 1301 63.82 -53.77 17/7/17 38.5 28031 ROV333 003 953 63.87 -53.29 20/7/17 19.5 16031 ROV333 004 953 63.87 -53.29 20/7/17 19 16031 ROV333 005 953 63.87 -53.29 20/7/17 18 16031 ROV333 046 704 63.87 -53.28 20/7/17 12 10031 ROV333 047 704 63.87 -53.28 20/7/17 10 9031 ROV333 048 704 63.87 -53.28 20/7/17 16 14031 ROV333 053 658 63.86 -53.28 20/7/17 19.5 16031 ROV333 054 658 63.86 -53.28 20/7/17 14.5 11031 ROV333 055 658 63.86 -53.28 20/7/17 6 6034 ROV334 001 940 63.87 -53.29 21/7/17 25 1034 ROV334 002 940 63.87 -53.29 21/7/17 10 2034 ROV334 003 940 63.87 -53.29 21/7/17 26 24034 ROV334 005 683 63.86 -53.28 21/7/17 18 11034 ROV334 006 683 63.86 -53.28 21/7/17 -- --034 ROV334 007 683 63.86 -53.28 21/7/17 20 1036 ROV335 001 1326 63.33 -52.78 22/7/17 11 10036 ROV335 002 1326 63.33 -52.78 22/7/17 11 1036 ROV335 003 1326 63.33 -52.78 22/7/17 10 1036 ROV335 004 1326 63.33 -52.78 22/7/17 12 12036 ROV335 041 1002 63.33 -52.77 22/7/17 17.5 1036 ROV335 043 1002 63.33 -52.77 22/7/17 14.5 11036 ROV335 073 845 63.33 -52.75 23/7/17 8 1036 ROV335 074 845 63.33 -52.75 23/7/17 13 1036 ROV335 075 845 63.33 -52.75 23/7/17 8 3037 ROV336 003 569 63.60 -52.92 23/7/17 21 19
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037 ROV336 005 549 63.60 -52.92 23/7/17 21.5 1037 ROV336 006 569 63.60 -52.92 23/7/17 23 1037 ROV336 032 497 63.60 -52.91 23/7/17 22.5 19037 ROV336 033 499 63.60 -52.91 23/7/17 20 17037 ROV336 034 499 63.60 -52.91 23/7/17 18 1037 ROV336 035 497 63.60 -52.91 23/7/17 19 1037 ROV336 042 381 63.61 -52.90 23/7/17 25.5 22037 ROV336 043 381 63.61 -52.90 23/7/17 20.3 1037 ROV336 044 349 63.61 -52.90 23/7/17 6 5037 ROV336 045 349 63.61 -52.90 23/7/17 11 1042 MGA004 002 519 63.55 -52.23 24/7/17 41 1042 MGA004 003 519 63.55 -52.23 24/7/17 41 1042 MGA004 004 519 63.55 -52.23 24/7/17 38 10042 MGA004 005 519 63.55 -52.23 24/7/17 35 10042 MGA004 006 519 63.55 -52.23 24/7/17 40 39042 MGA004 007 519 63.55 -52.23 24/7/17 41 80042 MGA004 008 519 63.55 -52.23 24/7/17 38 34042 MGA004 009 519 63.55 -52.23 24/7/17 35 15
TABLE28:SUMMARYOFSUBSAMPLESFROMSWGREENLAND.
Station Gear Event
WaterDepth(m)
Lat(DDS)
Long(DDS) Date
Maxlength(cm)
#Subsamples
049 MGA005 002 573 60.26 -46.89 27/7/17 38 1049 MGA005 003 573 60.26 -46.89 27/7/17 37 1049 MGA005 004 573 60.26 -46.89 27/7/17 36 16049 MGA005 005 573 60.26 -46.89 27/7/17 39 33049 MGA005 006 573 60.26 -46.89 27/7/17 37 64049 MGA005 007 573 60.26 -46.89 27/7/17 34 25049 MGA005 008 573 60.26 -46.89 27/7/17 36 11049 MGA005 009 573 60.26 -46.89 27/7/17 32 9050 ROV338 002 741 60.09 -46.63 28/7/17 20 16050 ROV338 003 742 60.09 -46.63 28/7/17 23.5 20050 ROV338 004 742 60.09 -46.63 28/7/17 20 1050 ROV338 005 742 60.09 -46.63 28/7/17 18 1050 ROV338 022 957 60.09 -46.64 28/7/17 12 9050 ROV338 023 957 60.09 -46.64 28/7/17 10 1050 ROV338 056 983 60.08 -46.64 28/7/17 24 20050 ROV338 057 983 60.08 -46.64 28/7/17 24 20050 ROV338 058 983 60.08 -46.64 28/7/17 22 1050 ROV338 059 983 60.08 -46.64 28/7/17 26 1051 MGA006 002 1326 60.12 -46.66 28/7/17 38 1051 ROV339 002 1085 59.93 -46.50 28/7/17 26 19051 MGA006 003 1326 60.12 -46.66 28/7/17 41 1051 MGA006 004 1326 60.12 -46.66 28/7/17 37 10
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051 MGA006 005 1326 60.12 -46.66 28/7/17 39 11051 MGA006 006 1326 60.12 -46.66 28/7/17 42 70051 MGA006 007 1326 60.12 -46.66 28/7/17 35 25051 MGA006 008 1326 60.12 -46.66 28/7/17 38 17051 MGA006 009 1326 60.12 -46.66 28/7/17 37 32052 ROV339 003 1085 59.93 -46.50 29/7/17 24 1052 ROV339 004 1085 59.93 -46.50 29/7/17 22.5 1052 ROV339 005 1085 59.93 -46.50 29/7/17 25 21052 ROV339 035 807 59.93 -46.50 29/7/17 17 15052 ROV339 036 807 59.93 -46.50 29/7/17 18.5 15052 ROV339 037 807 59.93 -46.50 29/7/17 23 1052 ROV339 038 807 59.93 -46.50 29/7/17 20 1052 ROV339 039 532 59.94 -46.51 29/7/17 14 12052 ROV339 040 532 59.94 -46.51 29/7/17 21.5 1052 ROV339 041 532 59.94 -46.51 29/7/17 12 1052 ROV339 042 532 59.94 -46.51 29/7/17 18.5 16057 MGA007 002 1286 59.46 -44.42 30/7/17 15 1057 MGA007 003 1286 59.46 -44.42 30/7/17 16 1057 MGA007 004 1286 59.46 -44.42 30/7/17 15 14057 MGA007 005 1286 59.46 -44.42 30/7/17 13 13057 MGA007 006 1286 59.46 -44.42 30/7/17 14 13057 MGA007 007 1286 59.46 -44.42 30/7/17 14.5 12057 MGA007 008 1286 59.46 -44.42 30/7/17 10 10057 MGA007 009 1286 59.46 -44.42 30/7/17 13 10061 GVY003 001 1669 59.00 -43.58 31/7/17 480 570062 GVY004 001 1608 58.94 -43.60 31/7/17 81.5 100063 GVY005 001 1907 58.61 -43.78 31/7/17 362 437
CoretopsamplesfrommegacoresandpushcoreswillbestoredatTheUniversityofBristolandgravitycoresampleswillbestoredattheBritishOceanSedimentCOreResearchFacility(BOSCORF).
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Chapter10:Biologicalsampling
FIGURE53:GHOSTSHRIMPFOUNDLIVINGINSIDEEUPLECTELLASPONGE.
Introduction
RemotelyOperatedVehicleoperationsweretheprimarytoolforbiologicalcollectionsonDY081.Everytimeasamplewascollecteditwasrecordedasaneventinthesampleeventlogandnotesweretakenaboutthetime,depth,latitude,longitude,physicaldescription(colour,sizeetc.),andanyinsituphotostakenofthespecimen.Onceondecksampleswerecarriedinpre-chilledseawaterintothecoldroom(4°C)tocommencesamplingtriage.EachcontainerontheROV(trayarea,net,biotubes,andbioboxes)thatcontainedspecimenswasgivenauniquenumber–thiswastheparentnumbertoeveryspecimenwithinthecontainer.Eachspecimenitselfwasthengivenauniquenumber,its“parentnumber”notedalongsideitseventnumber,ageneraltaxonomicdescription,anyfurthercommentsanddetailsofanysubsampletakene.g.forgeneticswork,dryingforisotopicresearch,etc.Mostspecimensweresub-sampledforgeneticanalysis(preservedin95%ethanol),theremainderofthespecimenwaspreservedineither100%ethanolorina-20°Cfreezer(withsomespecialconsiderationsforspongecollections,explainedbelow).Beforesub-samplingeachspecimenhadascaledpicturetaken.
Therewere1117lotsofspecimenscollectedtotalling1551specimensacross10Phyla(Figure55).
FIGURE54:ACESTASP.CLAMSBEINGCOLLECTED.
Ofthesecollections,severalwillformkeypartsoffuturepopulationgenomicanalyses.ThisincludesmembersoftheOphiuroidea,Psolussp.,Acestasp.(Figure54),Lopheliapertusa,Solenosmiliasp.,andAnthomastus.
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DY081CRUISEREPORT
FIGURE55:BREAKDOWNOFPHYLAFROMDY081.NOTE'CHORDATA'WEREEMPTYSHARKEGGCASESANDONEUNFORTUNATEHAGFISHSAMPLESINAMEGACORE.
CoralsAfterthediscoveryofLopheliaoffGreenlandin2011(Tendaletal.,2013;Kenchingtonetal,2017)itisunsurprisingthatassessmentofthesereefswasoneofthebiologicalaimsofDY081.Intotaltherewere315Cnidariacollected.Scleractiniaweretargetedforundergoingpopulationgenomic,phylogenomicandgeochemicalresearch(seeChapter11).
Althoughonly104werecollectedtherewereawidervarietyofOctocorallia,asseeninFigure56.Thesespecimenswillformpartofphylogenomicresearchthatiscurrentlyunderway.
FIGURE56:BREAKDOWNOFMAJOROCTOCORALLIAGROUPSCOLLECTEDONDY081.
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DY081CRUISEREPORT
ForfurtherdetailsaboutbiologicalcollectionspleasecontactDrMichelleTaylor:[email protected].
FIGURE57:ISIDIDAECORALFOUNDONORPHANKNOLL.
SpongesSpongecommunitiesatOrphanknollwerecharacterisedbyGeodiaspongegrounds(Figure58)withhexactinellid-dominatedcommunitiesinthedeeperareas(Figure59).AttheGreenlandsitescommunitiesseemedtohavemorediversedemospongecommunitiesandlargenumbersofencrustingspecies(Figure60).
FIGURE58:GEODIADOMINATEDSPONGECOMMUNITIESATORPHANKNOLL,ROV327,DEPTH2666M.
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DY081CRUISEREPORT
FIGURE59:HEXACTINELLIDDOMINATEDCOMMUNITYAT3440M,(ROV327).
FIGURE60:SPONGECOMMUNITIESONBEDROCK,GREENLAND,(ROV339).
Intotal291specimensofspongeswerecollected.Specimensthatwerelargeenoughweresubsampledasfollowing:
1) Geneticsamplefortaxonomy(95%ethanol)2) Geneticsampleforpopulationgenomics(95%ethanol)3) Drysampleforsiliconisotopework4) -80frozensampleforstudyofbacterialcommunities5) Remainderpreservedin95%ethanolorfrozenfortaxonomicwork.
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DY081CRUISEREPORT
AfewspecimenswerefrozenintactforstudyoftheirstructureandsamplesofspecimensfromGeodiapopulationsfromOrphanKnollwerefrozenformetabolomicwork(tobecarriedoutbyDrPacoCardenas,UppsalaUniversity,aspartoftheseparateSponGESproject.TaxonomicworkonthecommunitiesandstudyofspongestructurewillbeundertakenaspartofaPhDstudentshipattheUniversityofBristol(commencingautumn2017).InformationcollectedonROVdivesonspongecommunitieswillbeusedbyDepartmentofFisheriesandOceansCanadatoground-truthspeciesdistributionpredictionmodels.
FurtherinformationonspongescollectedcanbeobtainedfromDrClaireGoodwinclaire.goodwin@huntsmanmarine.ca.
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Chapter11:Scleractiniancorals
LiveandfossilscleractiniancoralswerecollectedfromOrphanKnoll,NuukandSouthGreenland.Coralswillbeanalysedasacollaborativeprojecttoexamine(paleo)biogeography,controlsofdeep-seacoralpopulations.Samplesofsuitableageswillbeusedforpaleoclimatestudiesofthepasthistoryoftheoceans.
SamplingProtocol
SampleswerecollectedusingtheROVusingthemanipulatorarms,theslurpgunorthroughusinganet.ThesampleswerebroughtondeckandintothecoldroomwheretheywerecategorisedusingBiologySpecimennumbers(seeChapter10).Aftersamplingforgeneticmaterialssampleswerecleanedanddried.Livespecimenswerebleached,rinsedanddriedtoremovetissue.Deadspecimenswererinsedinseawaterthenfreshwaterthenairdried.Sampleswerethencataloguedandpackedusingbiologyspecimennumbersandsub-divisions(a,betc.)wheremultiplesampleswererecoveredunderoneID(e.g.fromnets).
SamplingLocations
OrphanKnollSampleswererecoveredondives327,328,329,330and331.Livesolitarycoralsrangedindepthfrom2638mto1573m.Deadsolitarycoralswererecoveredfrom1826mto1581m.Deadcoralsweretypicallycoatedinthickblackferromangnesecrusts,unlesstheywererecoveredfromunderthesediment.Manyspecimenswereboredbyendolithicorganisms.Collectionsusingnetsprovedparticularlyeffectiveatcollectingfossilcoraldebrisfoundatthebaseofverticalfeatures(Figure61).
FIGURE61:FOSSILD.DIANTHUSINTHESEDIMENTATTHEBASEOFSMALLVERTICALWALLONORPHANKNOLL.LASERSSEPARATEDBY10CM.
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DY081CRUISEREPORT
NuukSampleswererecoveredondives333and334.Livesolitarycoralsrangedindepthfrom1216m-943m.Deadsolitarycoralswererecoveredfrom1171m-1107m.Livecolonialcoralsrangedindepthfrom1144-752m.Deadcolonialcoralswererecoveredfrom1231-761m.Deadcoralsrangedfromadarkbrownishcolourtoverypalewithlittleevidenceofboringorheavyferromanganeseencrustation(Figure62)
FIGURE62:DARKBROWNCOLONIALDEADCORALSFROMOFFSHORENUUK.SCALEBARINCMDIVISIONS.
SouthGreenlandSampleswererecoveredondives338and339.Livesolitarycoralsrangedindepthfrom1084-794m.Deadcolonialcoralswererecoveredfrom934m.Deadcoralswerebrownish,withlittleevidenceofboringorheavyferromanganeseencrustation.
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Chapter13:Microplasticssampling
Introduction
Microplastics(fibres)havebeenobservedinopenoceandeepseasediments.However,thedistributionandfluxesindifferentpartsoftheoceanarenotwellknown.WecollectedsedimentsfromDY081totestwhethermicroplasticsarealsoaccumulatingintheLabradorSea.ThecruiselocationsallowedforsamplingsedimentsfromOrphanKnoll,andfromGreenlandclosetoNuukandfurthersouth.MarinelitterwouldhavebeencollectedbytheROVifpossible,butsuchlitterwasrareandcouldnotbecollected,e.g.largefishingnet,anobjectthatappearedtobeatyrecompletelycolonisedbysponges.
Summaryofsamples
Ninecoreswerededicatedtomicroplasticswork,including6megacoresand3pushcores(Table30,overthepage).ThesamplesweredistributedacrossthethreemainworkingsiteswiththreeeachfromOrphanKnoll(3721-2152m),Nuuk(1301-519m)andsouthwestGreenland(1326-573m).
SampleacquisitionSedimentsformicroplasticswereeithercollectedbymegacoreorbypushcore.Drilledcoreswerenotselectedformicroplasticwork.Formegacoresapieceofcottonwasplacedoverthecoresbeforetherubberbungwasplavedonthecoretube.Sampleswerestoredandcoveredundercoldconditions,untiltheycouldbesubsampled.
SampleProcessing
Wholesedimentcoresweretakentobeprocessedinthe‘sealedlab’.Thesealedlabisasmalllabwhichwasclosedtootherpurposesandonlyenteredbytrainedpersonnel.Itwascleanedthoroughlyusingfilteredwateratthebeginningoftheexpedition,andbeforeeverysamplingactivity.Theairinletwascoveredwithcottontofilteroutplasticfibres.Wherepossibleplasticswereremovedfromthelaboratory,andanyplasticsintheroomwerethoroughlywashedbeforeentry.Samplersdonnedprotectivegear(cottonboilersuit)andthenstandardcoreslicingprocedureswerefollowedusinganallmetaldeviceforslicingthecore.Nogloveswereworntominimisethepossibilityofcontamination.Dampfilterpaperswereexposedtothelaboratoryenvironmentduringthecoreslicingprocesstoprovidebackgroundsamplesofambientcontamination.Allsedimentsliceswerewrappedinaluminiumfoil,thenplacedintoacardboardboxandremovedtoafreezer(orfridgeforthelastsampleswherefreezerspacewasnolongeravailable).SubsamplesandfiltercontrolsaresummarisedinTable30.
ThecorewillbeworkedbyincollaborationwithDrLucyWoodallfollowingestablishedproceduresfordeepseasediments.
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DY081CRUISEREPORT
NotesforcontaminationGravitycoresweretakenusingyellowplasticcoreliners.Openingthesecoresproducedlargeamountsofyellowplasticshavings.Thisworkwasperformedondeckandinthemainhanger.Crosscontaminationshouldbeminimisedbyperformingthesamplinginthesealedlab.However,fragmentsofthisdistinctyellowplasticshouldbeexcludedfromanyfuturemicroplasticcounts.
TABLE29:SUMMARYOFSAMPLESANDSUBSAMPLESTAKENFORMICROPLASTICSSTUDY.
Gear Event WaterDepth
Lat(Deg) Long(Deg) TotalLength(cm)
Numberofsamples
Lengthofsample(cm)
MGA001 006 3721 50.16 -45.51 36.5 10 2MGA001 006 na na na na 4blanks naROV327 47 2656 50.06 -45.36 13.5 7 2ROV327 47 na na na na 4blanks naROV327 68 2152 50.08 -45.36 18.5 9 2ROV327 68 na na na na 4blanks naMGA003 005 1301 63.82 -53.77 38 7 1MGA003 005 1301 63.82 -53.77 38 8 2MGA003 005 1301 63.82 -53.77 38 2 5MGA003 005 na na na na 3blanks naROV334 005 683 63.86 -53.28 18 8 1ROV334 005 683 63.86 -53.28 18 3 2ROV334 005 na na na na 3blanks naMGA004 009 519 63.55 -52.23 35 10 1MGA004 009 519 63.55 -52.23 35 5 2MGA004 009 na na na na 3blanks naMGA005 004 573 60.26 -46.89 36 11 1MGA005 004 573 60.26 -46.89 36 5 2MGA005 004 na na na na 3blanks naMGA006 008 1326 60.12 -46.66 38 9 1MGA006 008 1326 60.12 -46.66 38 5 2MGA006 008 1326 60.12 -46.66 38 2 5MGA006 008 na na na na 3blanks naMGA007 009 1286 59.46 44.42 13 10 1MGA007 009 na na na na 3blanks na
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DY081CRUISEREPORT
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