data acquisition and processing report for pa001€¦ · data acquisition and processing report for...

NOAAPacificMarineEnvironmentalLaboratory

OceanClimateStationsProject

DATAACQUISITIONANDPROCESSINGREPORTFORPA001

SiteName: OceanStationPapaDeploymentNumber: PA001

YearEstablished: 2007

NominalLocation: 50°N145°WAnchorPosition: 50.12°N144.84°W

DeploymentDate: June7,2007RecoveryDate: June10,2008

ProjectP.I.: Dr.MeghanF.CroninReportAuthors: J.A.Keene,M.F.Cronin,N.D.Anderson,

K.B.Ronnholm,andH.P.FreitagDataProcessors: S.Brown,P.Plimpton

DateofReport: August4,2017RevisionHistory: June30,2017

SpecialNotes: This mooring was established through support from the US NSF and NOAA, and incollaborationwiththeCanadianDepartmentofFisheriesandOceans(DFO)LinePProgram.

TableofContents

1.0 MooringSummary..........................................................................................................11.1 MooringDescription...........................................................................................................................21.2 InstrumentationonPA001..................................................................................................................4

2.0 DataAcquisition.............................................................................................................52.1 SamplingSpecifications.......................................................................................................................52.2 PrimaryDataReturns..........................................................................................................................62.3 KnownSensorIssues...........................................................................................................................7

3.0 DataProcessing..............................................................................................................83.1 BuoyPositions.....................................................................................................................................93.2 MeteorologicalData...........................................................................................................................9

3.2.1 Winds...........................................................................................................................................93.2.2 AirTemperature...........................................................................................................................93.2.3 RelativeHumidity.........................................................................................................................93.2.4 BarometricPressure...................................................................................................................103.2.5 Rain............................................................................................................................................103.2.6 ShortwaveRadiation.................................................................................................................103.2.7 LongwaveRadiation..................................................................................................................10

3.3 SubsurfaceData................................................................................................................................113.3.1 Temperature..............................................................................................................................113.3.2 Pressure.....................................................................................................................................123.3.3 Salinity.......................................................................................................................................123.3.4 Currents.....................................................................................................................................15

4.0 References....................................................................................................................16

5.0 Acknowledgements......................................................................................................16

6.0 ContactInformation.....................................................................................................16

APPENDIXA:DataQualityFlags...........................................................................................17

APPENDIXB:HighResolutionDataPlots..............................................................................18

APPENDIXC:PapaADCPSubsurfaceMooring.......................................................................22ListofTablesTable1:InstrumentsdeployedonPA001...................................................................................................4Table2:SamplingparametersofprimarysensorsonPA001......................................................................5Table3:SamplingparametersofsecondarysensorsonPA001..................................................................6ListofFiguresFigure1:PA001mooringpriortodeployment............................................................................................1Figure2:MooringpositionsaroundstationP26.........................................................................................2Figure3:PA001mooringdiagram...............................................................................................................3Figure4:Linearcorrectionsappliedto1msalinitydata...........................................................................14

www.pmel.noaa.gov/ocs PA001

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DataAcquisitionandProcessingReportforOCSMooringPA001

1.0 MooringSummaryTheNOAAOceanClimateStationssurfacemooringatOceanStationPapawasinitiatedthroughaNationalScienceFoundationCarbonandWater in theEarthSystemproject"North Pacific Carbon Cycle" to Dr. S. Emerson (UW). NOAA in-kind support wasprovided through the Office of Ocean and Atmospheric Research. The mooringdeployment and servicing occurred in collaboration with the Fisheries and OceansCanada,PacificRegion,Line-PProgramaboardtheCCGSJOHNP.TULLY.OCSisthankfulforthegenerousshiptimeprovidedbyFisheriesandOceansCanada,aspartofacruiseheaded by the Institute of Ocean Sciences (IOS). The captain, crew, and scientistsaboardarealsogratefullyacknowledgedfortheircontributions.ThePA001mooringwasdeployedinJune2007atOceanStationPapatomonitorocean-atmosphere interactions, carbonuptake,andoceanacidification. PA001was the firstNOAAOCSdeploymentatthissite.Itwasoriginallyintendedtobea9-monthmooring(deployedJune2007andrecoveredFebruary2008)sincethepHsensorwasknowntoperform poorly past that period. Due to weather, however, no mooring operationscould be completed on the February 2008 cruise. A second turnaround cruise wassuccessfully completed in June 2008. Since then, OCS has maintained a 1-yearturnaroundscheduleontheLine-PJunecruises.

Figure1:PA001mooringpriortodeployment.


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AseparatesubsurfaceADCPmooringwasanchored7.7kmfromthePA001anchor.Themap below shows the mooring locations, and additional details on the subsurfacemooringcanbefoundinAppendixC.

Figure2:MooringpositionsaroundstationP26.

1.1 MooringDescriptionThe PA001 mooring was a taut-line mooring, with a nominal scope of 0.985. Non-rotating7/16”(1.11cm)diameterwirerope,jacketedto1/2"(1.27cm),wasusedintheupper 16.4mof themooring line. A break in thewire,with 3/4” chain,was used tomountaCTD/GTD/O2instrumentpackageat20m.Thiswasfollowedbyanother679mofwire ropeused tomountadditional subsurface instruments. The remainderof themooringconsistedofplaited8-strandnylonlinetotheacousticreleaseinlineabovetheanchor.The6,850lb(3,107kg)anchorwasfabricatedfromscraprailroadwheels.The surface buoywas a solid-hull fiberglass-over-foamdiscus buoy,with awatertightcenterwell. It hadanaluminum toweranda stainless steelbridle. No load cellwasdeployedonPA001.ACO2fluxmonitoringsystemwasalsodeployedonthePA001mooring,incollaborationwiththePMELCarbonGroup.OCSisnotresponsiblefortheacquisitionorprocessingofthesedata.Nofurtherdiscussionofthatsystemisincludedinthisreport.ForfurtherinformationonthePapabiogeochemistrydata,seehttp://www.pmel.noaa.gov/co2/.


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Figure3:PA001mooringdiagram.


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1.2 InstrumentationonPA001The following instrumentation was deployed on PA001. Redundant data acquisitionsystems were used; ATLAS and Flex. ATLAS meteorological sensors were consideredprimary,exceptincaseswhereasensorwasonlydeployedontheFlexsystem(e.g.BP).DEPLOYMENT: PA001 Met Sensors Serial # Notes Height Acquisition ATLAS 685 w/ C100 compass

2.6m ATRH Rotronics MP101 59287 3.6m Rain RM Young/50203 882 3.6m SWR Epply PSP 31649 3.6m LWR Epply PIR 33346 4.2m Wind Gill Windsonic 51415

Acquisition Flex 0001

3.7m Wind Gill Windsonic 52263 2.6m BP Paroscientific/MET1-2 99453

CO2 Electronics PMEL 0017

Span gas JA02402 419.61 ppm CO2 Subsurface Bridle

1m SSC ATLAS SSTC Module 14128 1m pH SAMI (UW) 56 1m CTD/GTD/O2 SBE16+ (UW) 5105

Depth

5m TC ATLAS TC Module 11162 Inverted 7m Current mtr Sontek Argonaut 521

8.3m TCV ATLAS TCV Module 12986 10m TC ATLAS TC Module 11167 Inverted 15m TC ATLAS TC Module 11168 Inverted, knocked out of mount

16.7m Current mtr Sontek Argonaut 554 Top clamp broken on dep. 18m TV ATLAS TV Module 12604 Last inductive sensor on wire 20m CTD/GTD/O2 SBE16+ 5106 (UW) 25m TC Seabird SBE-51TC 0004 30m T ATLAS T Module 12632 Inverted 32m Current mtr RDI DVS 0014 Downward, ended early 35m TC ATLAS TC Module 11571 Inverted 37m Current mtr Sontek Argonaut 571 Upward 45m TC ATLAS TC Module 11608 Inverted 60m TC Seabird SBE-51TC 0005 80m TC ATLAS TC Module 14086

100m TC ATLAS TC Module 14087 120m TC ATLAS TC Module 14306 150m TC ATLAS TC Module 14333 200m TC ATLAS TC Module 14334 300m TP ATLAS TP Module 14166

Table1:InstrumentsdeployedonPA001.


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2.0 DataAcquisitionTwo independentdataacquisitionsystemsweredeployedonPA001. TheATLASdataacquisition system transmits daily average and intermittent spot meteorologicalmeasurementstoshorethroughServiceArgossatellites. TheFlexsystemusesIridiumsatellitecommunicationstotransmithourlydata.ForPA001,ATLASwasconnectedtothesubsurfaceinstruments(above18m)usinganinductiveline.Highresolutionsurfacedatafromtheacquisitionsystems,aswellasinternallyloggeddatafromthesubsurfaceinstruments,weredownloadeduponrecoveryofthemooring.TheATLASsystemdoesnotacquireorstorepositioninformation,butbuoypositionsareprovidedbytheServiceArgossatellites.Whenfourormoresatellitesareinthebuoy’sfield of view during data transmissions, the satellites assess the Doppler shift of theknowntransmissionfrequencytogenerateestimatesof latitudeand longitude. Theseopportunisticpositionestimatesarethenappendedtothedatatransmissions.More accurate Global Positioning System (GPS) data were also acquired andtelemetered to shore, via two Iridium Positioning beacon Systems (IPS) on the buoy.GPS/IPSpositionswererecordedbytheFlexsystematapproximatelysix-hourintervals.

2.1 SamplingSpecificationsThetablesbelowdescribethehigh-resolutionsamplingschemesforthePA001mooring.Observationtimesindatafilesareassignedtothecenteroftheaveraginginterval.

PRIMARYSENSORS

Measurement SampleRate

SamplePeriod

SampleTimes

RecordedResolution

AcquisitionSystem

WindSpeed/Direction 2Hz 2min 2359-0001,0009-0011… 10min ATLAS

AirTemperature/RelativeHumidity 2Hz 2min 2359-0001,

0009-0011… 10min ATLAS

BarometricPressure 1Hz 2min 2359-0001,0009-0011… 10min Flex

RainRate 1Hz 1min 0000-0001,0001-0002… 1min ATLAS

ShortwaveRadiation 1Hz 2min 2359-0001,0001-0003… 2min ATLAS

LongwaveRadiation(Thermopile,Case&DomeTemperatures)

1Hz 2min 2359-0001,0001-0003… 2min ATLAS

SeawaterTemperature,Pressure

&Conductivity

1per10min Instant. 0000,

0010,… 10min Internal

UWCTD(1m/20m) 1perhour Instant. 0000,

0100,… 1hour Internal

OceanCurrents(Point) 1Hz 2min 2359-0001,

0019-0021… 20min Internal

Table2:SamplingparametersofprimarysensorsonPA001.


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SECONDARYSENSORS

Measurement SampleRate

SamplePeriod

SampleTimes

RecordedResolution

AcquisitionSystem

WindSpeed/Direction 1Hz 2min 2359-0001,0009-0011… 10min Flex

GPSPosition 1per6hrs Instant. ~0030,

~0630,… ~6hrs Flex

Table3:SamplingparametersofsecondarysensorsonPA001.

2.2 PrimaryDataReturnsATLAS Tube 685, software version 4.10: Wind 51415 96.7% AirT 59287 96.7% RH 59287 61.2% SWR 31649 96.7% Rain 882 95.4% LWR 33346 96.7% 65 flags (Flex) BP 99453 69.7% (from raw flash data) Modules: 1m SSC #14128 100% t, 99.2% c 1m SBE16+ #5105 74.0% t, 74.0% c 5m TC #11162 46.3% t, 46.3% c battery died 8m TCV #12986 100% t, 99.9% c 10m TC #11167 100% t&c 15m TC #11168 0% lost 18m TV #12604 0% flooded beyond repair 20m SBE16+ #5106 91.9% t, 91.9% c 30m T #12632 100% 35m TC #11571 100% t&c 45m TC #11608 100% t&c 80m TC #14086 100% t&c 100m TC #14087 100% t&c 120m TC #14306 100% t&c 150m TC #14333 100% t&c 200m TC #14334 100% t&c 300m TP #14166 100% t&p


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2.3 KnownSensorIssuesOnJanuary17,2008[017],theRHdatabecameintermittent,reportingvaluesthatwereincreasingly out of bounds. Data measured >100% was not reported by the sensor(1E+34, equivalent to Q5). Water damage was found under the filter cap when thesensorwasrecovered.The rain gauge failed on September 28, 2007 [271]. The instrument reported 0accumulationandindicatedahigh%timeraining.Raindatawereflaggedasbadafterthisdate.Although real-time data from the 7m Sontek (measuring at 5m depth) was flagged1E+35May17,2008[138],thefulldelayedmoderecordwasrecovered,andstandardqualityflagsofQ2wereassigned.ADVSdeployedat32mfailedonSeptember28,2007[271],lessthan1/3rdofthewaythroughthedeployment.Batteryfailureissuspected,astheyweredeaduponrecovery.The5mmodulestoppedsendingreal-timedataduetoadeadbattery,butthedelayed-mode data were salvaged up until its failure. The 15m module was missing uponrecovery,sonohigh-resolutiondatawereavailable.TheTVmoduleat18mwasfoundfloodeduponrecovery. Real-timedatafromtheTVmoduleendedonJune9,2007[160],shortlyafterthedeployment.Nohigh-resolutiondatawereavailable.TheTVcabletothe17mSontekwasfoundtohaveparted,andtheSontekwasmissing.TheATLASdataacquisition systemdropped intoa “failsafe”modeas its logicbatterywasfailingandstoppedstoringdatatomemoryonMay29,2008[150],justdaysbeforerecovery. The last transmitted diagnostic indicated the logic and transmit batteries,weredownto5.7and8.8volts,respectively.Nohigh-resolutionprimarymeteorologicaldata were recorded afterMay 29th, explaining themaximum surface data returns of96.7%.TheFlexdataacquisitionsystemfailedonMarch8th,2008[068],duetoadeadbattery.Thefinaltelemetereddiagnosticshowedthatthebatteryhaddroppedto7.5volts.TheFlexsystemcontrolledtheprimarybarometricpressuresensorandthesecondarywindsensor,sodatafrombothinstrumentsendedatthetimethebatteryfailed.Additional damage was found after recovery on June 10, 2008 [162]. The radiationsensorshieldswereslightlybent,andtherubberbumperwaspartiallytornoffthebuoyhull. TheSBE51TCinstrumentsat25mand60mwereunresponsive.Theinstrumentswere sent to SBE, but there are no indications that any high-resolution data wererecovered. Since these instrumentswerebelow the inductiveportionof thewire,noreal-timedatawerecapturedeither.


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3.0 DataProcessingProcessingofdatafromOCSmoorings iscontractedtothePMELTropicalAtmosphereOcean(TAO)projectgroup.Dataprocessingfollowsthemethodsdescribedbelow.Theprocess includedassignmentofqualityflagsforeachobservation,whicharedescribedinAppendixA.Anyissuesordeviationsfromstandardmethodsarenotedinprocessinglogs,andinthisreport.Rawdatarecoveredfromthe internalmemoryofthedataacquisitionsystemarefirstprocessedusing computer programs. Pre-deployment calibrations are applied to rawATLASdata (recordedassensorcounts), togenerateadatatimeseries inengineeringunits. Instrumentation recovered inworking condition is returned to PMEL for post-recoverycalibrationbeforebeingreusedonfuturedeployments. Thesepost-recoverycalibration coefficients are compared to the pre-deployment coefficients. If thecomparisonindicatesadriftgreaterthantheexpectedinstrumentaccuracy,thequalityflagisloweredforthemeasurement.Ifpost-recoverycalibrationsindicatethatsensordriftwaswithinexpectedlimits,thequalityflagisraised.Post-recoverycalibrationsarenotgenerallyappliedtothedata,exceptforseawatersalinity,orasotherwisenotedinthisreport.Failedpost-recoverycalibrationsarenoted,alongwithmodeoffailure,andquality flags are left unchanged to indicate that pre-deployment calibrations wereappliedandsensordriftwasnotestimated.Theautomatedprogramsalsosearchformissingdata,andperformgrosserrorchecksfordata that fall outsidephysically realistic ranges. A computer logofpotential dataproblemsisautomaticallygeneratedasaresultoftheseprocedures.Time series plots, spectral plots, and histograms are generated for all data. Plots ofdifferences between adjacent subsurface temperature measurements are alsogenerated. Statistics, including the mean, median, standard deviation, variance,minimumandmaximumarecalculatedforeachtimeseries.Individualtimeseriesandstatisticalsummariesareexaminedbytrainedanalysts.Datathathavepassedgrosserrorchecks,butwhichareunusualrelativetoneighboringdatainthetimeseries,orwhicharestatisticaloutliers,areexaminedonacase-by-casebasis.Mooringdeploymentandrecoverylogsaresearchedforcorroboratinginformationsuchasbattery failures,vandalism,damagedsensors,or incorrectclocks. Consistencywithothervariablesisalsochecked.Datapointsthatareultimatelyjudgedtobeerroneousareflagged,andinsomecases,valuesarereplacedwith“outofrange”markers.Forafulldescriptionofqualityflags,refertoAppendixA.For some variables, additional post-processing after recovery is required to ensuremaximumquality.Thesevariable-specificproceduresaredescribedbelow.


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3.1 BuoyPositionsSincePapaisataut-linemooringwithashortscope,thebuoyhasasmallwatchcircleradiusof1.25km. WhenusingPapadata inscientificanalyses,thenominalpositionisusuallyadequate. Foruserswantingadditionalaccuracy, themoreaccuratepositionsfrom GPS/IPS are also provided at their native resolution. Gross error checking wasperformedtoeliminatevaluesoutsidethewatchcircle,butnofurtherprocessingwasperformed.

3.2 MeteorologicalDataTheATLASdataacquisition systemstopped storingdata tomemoryonMay29,2008[150],justdaysbeforerecovery.Nohigh-resolutionprimarymeteorologicaldatawererecordedafterthistime.Data from secondary sensors are not included in the final data sets, except whenprovidedinOceanSITESformat.

3.2.1 WindsTherecoveredhighresolutionwindspeedsfromtheGillsensorwereinunitsof0.1m/sper count rather than 0.2m/s per count from the real-time data. Coefficients wereadjustedduringprocessingtoobtainthecorrectvelocities.

3.2.2 AirTemperatureTherearenospecialprocessingnotesforairtemperatureatPA001.Refertosection3.0forgeneralremarks.

3.2.3 RelativeHumidityThe relative humidity data contained 18,782 1E+34 (out of the 0-100% range) valuesstartingon January17,2008 [017]. The instrumentalternatedbetweenhighand lowhexvalues (FFand00). Thereafter, the sensor reporteda fewdatapoints justbelow100%,asifthemeancurvehadshiftedupover100%,maxingoutthesensor.Thereareno historic or adjacent data for comparison, but the othermeteorological datawerecomparably seasonal. The air temperature data matched the longwave radiationsensor’s case and dome temperature data very well, and there were numerous rainevents matching the high relative humidity. It is assumed that sensor damage firstoccurredJanuary17,2008[017],andthedatawereleftwithdefaultqualityflagspriortothistime.Therelativehumiditysensorfailed itspostrecoverycalibration. Itwasnotedthatthemeasuredvaluesrampedupsharplyathigherhumiditylevelsduringthecalibrationrun.Waterdamagewasfoundunderthefiltercap.


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3.2.4 BarometricPressureTheBPsensoronPA001failedonMarch8th,2008,astheFlexsystem’sbatterypowerbecamedepleted. Nodataexistsafter thisdate,as theBPsensordoesnot internallyrecorddata.

3.2.5 RainRaindataareacquiredasaccumulationvalues,andthenconvertedtorainratesduringprocessing. Rainfall data are collected using an RM Young rain gauge, and recordedinternally at a1-min sample rate. Thegauge consistsof a500mL catchment cylinderwhich,when full, emptiesautomatically viaa siphon tube. Data froma threeminuteperiod centered near siphon events are ignored. Occasional random spikes in theaccumulationdata,whichtypicallyoccurduringperiodsof rapidrainaccumulation,orimmediatelyprecedingorfollowingsiphonevents,areeliminatedmanually.Toreduceinstrumentalnoise,internallyrecorded1-minuterainaccumulationvaluesaresmoothed with a 16-minute Hanning filter upon recovery. These smoothed data arethen differenced at 10-minute intervals and converted to rain rates in mm/hr. Theresultant rain rate valuesare centeredat times coincidentwithother10-minutedata(0000,0010,0020...).Residualnoiseinthefiltereddatamayincludeoccasionalnegativerainrates,buttheserarely exceed a fewmm/hr. Nowind correction is applied, as this is expected to bedoneby theuser. Thewindeffect canbe large. According to theSerra,etal (2001)correction scheme, atwind speeds of 5m/s the rain rates should bemultiplied by afactorof1.09,whileatwindspeedsof10m/s,thefactoris1.3.The PA001 rain data contained 209 sporadic 1E+34 (out of range) values starting at22:10onMay27,2008[148].Inaddition,thedatashowedthicksmall-scalenoiseandsome large spikes, just before theATLAS tube stopped storing data. While rain datausuallycontainssomenoise,additionalnoisecouldhavebeenduetothedyingbatteryandATLAStubefailure.Smalldiurnalspikesappearedinthedataatnoonandmidnight,withafewlargespikesscatteredthroughoutthedata.Thesewereremovedduringqualityflagging,alongwiththethicksmall-scalenoiseandlargespikesmentionedabove.Theinstrumentpassedabenchtestafterrecovery.

3.2.6 ShortwaveRadiationThere are no special processing notes for shortwave radiation at PA001. Refer tosection3.0forgeneralremarks.

3.2.7 LongwaveRadiationThe downwelling longwave radiation is computed from thermopile voltage, dometemperature, and instrument case temperature measurements, using the methoddescribedbyFairalletal.(1998).


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The longwave radiation data contained 65 1E+34 (out of range) values scatteredrandomlythroughoutthelasttwodaysofdata,startingat22:10onMay27,2008[148].ThiswaslikelyrelatedtothefailingATLAStube.

3.3 SubsurfaceDataWhentheATLAS tubestoppedcommunicatingwith themonMay29,2008 [150], themodule clocks began drifting. At recovery, they were all found to be slow by 8-19minutes. Anautomatedscriptwasusedto linearly interpolatethedatatothecorrecttimestamps,betweenthestartofthedriftandtheendofthedatafiles(from00:00ZonMay 29, 2008 to 16:30Z on June 13th, 2008). The temperature, pressure, salinity,conductivity, anddensity fileswereall adjusted, andwere flaggedwithQ3 (adjusted)duetotheinterpolation.Subsurfaceclockdrifts(inminutes,negative=slow):Depth: ClockDrift: 1m -8.32 5m Notmeasured(lowbattery) 8m -8.6 10m -8.38 15m Lostbeforerecovery 18m Flooded 20m Notinitiallyobtained(bothUWinstrumentswerelatercorrectedby+7hrs) 30m -8.13 35m -11.13 45m -12.05 80m -11.2 100m -11.63 120m -9.43 150m -18.75 200m -9.85 300m -12.57Since 2007, themeasurement point for SST/C is known to have varied between1.0 -1.3mdepth. Uncertainties inactualmeasurementdepthare introducedbychanges inbuoy waterlines, variation between instrumentmounting locations, and alteration ofmeasurementpointswithdifferentinstrumentversions.Forthesereasons,thenominaldepthfortheSST/Cmeasurementisstatedas1m.

3.3.1 TemperatureTherewerenumeroustemperatureinversionsinthe80m-150mtemperatures,butnocorrespondingdensityinversions,sonotemperatureadjustmentsweremade.


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Temperature sensors typically have negligible drift over the course of a deployment.Accuracy,whichincludessensordrift,islistedas±0.02°CforATLASmodules.Nopost-calibrationadjustmentswereappliedduringprocessing.SeeSection3.3.2foradditionalnotesabouttemperaturequalityflags.

3.3.2 PressureSincethiswasatautmooring,actualpressuresareexpectedtobeclosetothepressuresatnominaldepths.Therewasonlyonepressuresensoronthemooringline,theSBE39-TP at 300m. There were no spikes seen in the 300m pressures attributable tovandalism. However, the baseline of the pressures sat right at the lower pressureboundof305dBthroughoutthedeployment.Therewerenonotesintherecoverylogtoindicatethatthemodulewasfounddeeperthanitsnominaldepth.Itispossiblethesensorwasreadingslightlylow,butnoadjacentpressuremeasurementswereavailabletoconfirm.Thepercentofdataout-of-boundswas20.98%.Temperatureandsalinityvaluesforalldepthsbelow1m,correspondingtotheout-of-range pressures, were assigned Q4 quality flags for potentially being out of theirnominaldepths.

3.3.3 SalinitySalinityvalueswerecalculatedfrommeasuredconductivityandtemperaturedatausingthemethodofFofonoffandMillard (1983). Conductivityvalues fromalldepthswereadjustedforsensorcalibrationdriftby linearly interpolatingovertimebetweenvaluescalculatedfromthepre-deploymentcalibrationcoefficientsandthosederivedfromthepost-deploymentcalibrationcoefficients. Salinitieswerecalculated fromboth thepreandpostconductivityvaluestodeterminethedriftinthesalinitymeasurement.SalinityDriftsinPSU(post-pre):Depth: Drift:1m 0.01185m 0.00008m -0.000810m 0.022915m Lost35m 0.007545m 0.018780m 0.0030100m 0.0092120m -0.0145150m 0.0009200m 0.0208 *Negativevaluesindicatescouring;positivevaluesindicatefouling.


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The values above indicate the change in calculated salinity data values when post-recoverycalibrationswereappliedtotheconductivitymeasurement,versuswhenpre-deploymentcalibrationswereapplied.Negativedifferencessuggestthattheinstrumentdrifted towards higher values while deployed, and indicate expansion of theconductivity cell’s effective cross-sectional area. This expansion is possibly due toscouringofthecellwallbyabrasivematerialintheseawater.Positivevaluesindicateadecrease in the cell’s effective cross-sectional area, presumably due to fouling, andsecondarilyduetofoulingorlossofmaterialonthecellelectrodes.AthirteenpointHanningfilterwasappliedtothehigh-resolution(tenminuteinterval)conductivity and temperature data. A filtered value was calculated at any point forwhich seven of the thirteen input points were available. The missing points werehandled by dropping theirweights from the calculation, rather than by adjusting thelengthofthefilter.Salinityvalueswerethenrecalculatedfromthefiltereddata.

ManualSalinityAdjustmentsThe drift-corrected salinities were checked for continuity across deployments. Theinstrumentsand1mand45mcomparedwellwithsalinitymeasurementsonPA002,sonoadjustmentsweremade.Sensorswerenotdeployedatanyothermatchingdepthsbetweenthetwoyears.Additional linear corrections were also applied to the salinity data in time segmentsacrossthedeployment.Thesecorrectionswerebasedoncomparisonswithneighboringsensorsonthemooringline.Ifanunrealisticprolonged,unstabledensityinversionwasfound,anattemptwasmadetoidentifythesensoratfaultandadjustitsdatabasedondifferenceswith data from adjacent depths during unstratified conditions (e.g.withinthemixedlayerduringnighttime).TheseinsitucalibrationproceduresaredescribedbyFreitagetal.(1999).As noted in Section 3.3.1, therewere numerous temperature inversions in the 80m -150mtemperaturesforPA001,butnocorrespondingdensityinversions. Severalsmalldriftcorrectionsweremadetothe1msalinities.Startandendpointsoftheadjustmentsegments shown below are in the format of Year, Year day, Hour, Minute, Second(YYYYDDDHHMMSS). The adjustment amounts listed were applied linearly to themeasuredvaluesoverthattimeperiod,asshowninFigure4.1mSalinityAdjustments2007185031000-2007225090000 0.000->0.0852007225091000-2007250170000 0.085->0.0852007250171000-2007272133000 0.085->0.1222007272134000-2008071000000 0.122->0.1222008071001000-2008090090000 0.122->0.1302008090091000-2008151233000 0.130->0.1692008151234000-2008162163000 0.169->0.200


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Figure4:Linearcorrectionsappliedto1msalinitydata.

The high-resolution salinity measurements at 1m and 8m contained noise that wasflagged (1E+33, equivalent toQ5). Flagging started at September14, 2007 [257] andNovember9,2007[313]forthe1mand8mdata,respectively.Thesectionsofflaggeddata were short enough that they only impacted the hourly data. The final dailyaverageswerenotaffected.Additional salinity measurements were available from two CTD/GTD/O2 instrumentsprovidedbytheUniversityofWashington,deployedat1mand20monPA001.The20minstrumentwasconsideredprimary,but since the1m instrumentwas redundantwiththe1mSSTC,itwasclassifiedassecondary.Salinitydrift(postcaldata-precaldata)forUWinstruments:1m0.012020m0.0569 *Negativevaluesindicatescouring;positivevaluesindicatefouling.Smalllinearadjustmentsweremadetoeachdataset:1m:2007158230000-2008067110000 -0.011->-0.02620m:2007158230000-2008133130000 0.000->-0.06


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Bothsetsofdata fromtheUWinstrumentsendedearly. The1mdataended inearlyMarch, and the20mdataended inearlyMay. Whendata from theUW instrumentswere plotted alongside data from adjacent instruments, a 7 hour time offset wasdiscovered throughout thedeployment, likely due to incorrectly set clocks. The timestampsfromtheUWinstrumentswereadjustedforwardby7hoursinthefinalfilestocorrect theoffset. NoHanning filterwasappliedto theUWinstrumentdata,as theirhighestresolutiondatawasalreadyhourly.ACTDcastwasperformednearthePA001mooring. Data fromthemooringandCTDcastcomparedfavorably,giventhemeasurementsweretaken10NMapart.

3.3.4 CurrentsPointcurrentmetersweredeployedatfourdepthsonthePA001mooring.Thestatedhead depth differs from the actual current measurement depth, because theinstrumentsrequireablankingdistance.Currentsfromtheinstrumentsdeployedat7,16.7, 32, and 37mmeasured velocities at 5, 15, 34, and 35m, respectively. The 32minstrument was an RDI DVS current meter, which failed early, while the remaininginstruments were Sontek current meters. Since the PA001 mooring line was taut,currentmeterswerenotcorrectedfornegligiblebuoymotion.The current meters on PA001 measured the speed of sound, and internally appliedsound velocity corrections to current measurements. During post-processing, acorrectionformagneticdeclinationwasapplied.A(thirteen/seven)pointHanningfilterwasappliedtothe (DVS/Sontek)dataat (10/20)minuteresolutiontogethourlydata,andaboxcar filterwas applied to thehigh resolutiondata toproducedaily averagedvalues.The Sontek current meter at 16.7m was lost, and its corresponding TV module wasflooded,sonohigh-resolutiondatawererecovered. Real-timedataendedonJune9,2007[160],beforeanydailyaverageswerecomputed.TheSonteksat7mand37mhad100%datareturn.Duringprocessing,verylargetidalvelocities (upto0.65m/s)werenoted. Thismadecomparisonswith thenearbyADCPmooring difficult. The comparison did indicate a difference of up to 2° in the ADCPcompass, but since both instrument models have compass accuracies of ±2°, this iswithinaccuracyspecifications.TheSontekshad8to11minuteclockerrorsbytheendofthedeployment,butthiswasnot adjusted in the data. It is not knownwhether the drift occurred gradually, andinterpolatingfortimedriftstendstodiminishdataquality.Also,qualityflagswerenotsettoQ4fortimeswhenthe300mpressurewasoutofrange.


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4.0 ReferencesFairall,C.W.,P.O.G.Persson,E.F.Bradley,R.E.Payne,andS.P.Anderson,1998:AnewlookatcalibrationanduseofEppleyPrecisionInfraredRadiometers.PartI:TheoryandApplication.J.Atmos.Ocean.Tech.,15,1229-1242.Freitag,H.P.,M.E.McCarty,C.Nosse,R.Lukas,M.J.McPhaden,andM.F.Cronin,1999:COARE Seacat data: Calibrations and quality control procedures. NOAA Tech.Memo.ERLPMEL-115,89pp.Fofonoff,P.,andR.C.MillardJr.:Algorithmsforcomputationoffundamentalpropertiesofseawater,Tech.Pap.Mar.Sci.,44,53pp.,Unesco,Paris,1983.Serra,Y.L.,P.A'Hearn,H.P.Freitag,andM.J.McPhaden,2001:ATLASself-siphoningraingaugeerrorestimates.J.Atmos.Ocean.Tech.,18,1989-2002.

5.0 AcknowledgementsDr.SteveEmerson(UW)was leadPI for theNSFproject that fundedthisdeployment.TheOCSprojectoffice isgrateful forhisvisionandefforts tomake theNOAAsurfacemooringatStationPapapossible.TheOCSprojectofficethankstheLinePprogramforprovidingshiptime,ChiefScientist,MarieRobert,andthecaptainandcrewoftheCCGSJOHNP.TULLYforthedeploymentand recovery of this mooring. D. Zimmerman and P. A’Hearn (both of UW JISAO)participatedinthedeploymentcruise.P.A’HearnandLCDRR.Kamphaus(NOAACorp)participated in the February 2007 recovery cruise (where nomooring work could becompleted due to weather) and P. A’Hearn participated in the successful June 2008recoverycruise.S. Brown (UW JISAO) processed ATLASmeteorological data, subsurface temperature,pressureandconductivity/salinitydata.P.Plimpton(NOAAPMEL)processedtheNP001ADCP data and current meter data, with additional work on the current meter datadonebyC.Feyin2014.

6.0 ContactInformationFormoreinformationaboutthismooringanddataset,pleasecontact:[email protected]/PMEL/OCS7600SandPointWayNESeattle,WA98115


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APPENDIXA:DataQualityFlagsInstrumentation recovered in working condition is returned to PMEL for post-recoverycalibration before being reusedon future deployments. The resultant calibration coefficientsare compared to the pre-deployment coefficients, and measurements are assigned qualityindicesbasedondrift,usingthefollowingcriteria:Q0- NoSensor,orDatumMissing.Q1- HighestQuality.Pre/post-deploymentcalibrationsagreetowithinsensorspecifications.

Inmostcases,onlypre-deploymentcalibrationshavebeenapplied.

Q2- Default Quality. Pre-deployment calibrations only or post-recovery calibrations onlyapplied.Default value for sensorspresentlydeployedand for sensorswhichwerenotrecoveredornotcalibratablewhenrecovered,orforwhichpre-deploymentcalibrationshavebeendeterminedtobeinvalid.

Q3- AdjustedData.Pre/postcalibrationsdiffer,ororiginaldatadonotagreewithotherdatasources (e.g., other in situ data or climatology), or original data are noisy. Data havebeenadjustedinanattempttoreducetheerror.

Q4- LowerQuality.Pre/postcalibrationsdiffer,ordatadonotagreewithotherdatasources(e.g.,otherinsitudataorclimatology),ordataarenoisy.Datacouldnotbeconfidentlyadjustedtocorrectforerror.

Q5- Sensor,InstrumentorDataSystemFailed.For dataprovided inOceanSITES format, the standardTAOquality flagsdescribedabove aremappedtothedifferentOceanSITESqualityflagsshownbelow:Q0- NoQCPerformed.Q1- GoodData. (TAOQ1,Q2)Q2- ProbablyGoodData. (TAOQ3,Q4)Q3- BadDatathatarePotentiallyCorrectable.Q4- BadData. (TAOQ5)Q5- ValueChanged.Q6- NotUsed.Q7- NominalValue.Q8- InterpolatedValue.Q9- MissingValue. (TAOQ0)


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APPENDIXB:HighResolutionDataPlots

FigureB1:PA001subsurfacetemperature,salinity,anddensityathourlyresolution(decimated).


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FigureB2:PA001highresolution(10-min)primarysurfacemeteorologicaldata.


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FigureB3:PA001highresolution(2-min)radiationdata.


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FigureB4:Zonalandmeridionalcurrentmeterdata(decimated)fromPA001.The16.7mSontekwaslost,andthe32m(measuringat35m)DVSdatawascutshortduetodeadbatteries.TheDVSdataoverlappedthe35mSontekdataseeninthisfigure,andthemorecompleteSontekrecordwasconsideredprimary.


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APPENDIXC:PapaADCPSubsurfaceMooring

MooringDescriptionAseparatesubsurfacemooring(NP001)wasdeployedinproximitytoPA001thatcontaineda150KHz, upward-looking ADCP at a nominal depth of 160m and nominal position of 50.12N,144.97W. Deployed 6/6/07 and recovered 6/9/08, an ADCP (SN 542) on loan fromNOAA’sPMEL ECO FOCI group recorded data over a depth range of 28-160m in 2m bins. The pre-deployment file, confirmed by RDI technicians, indicates that there were 300 pings perensemble,withaping intervalof3second, tocenterdataonthehour. FigureC1showsthemooringdiagramofthisdeployment,butthedepthsareapproximately19mtooshallowduetoincorrectmooringlinelengths,whichplacedtheactualheaddepthof164mnearthenominaldepth.TheNP001mooringalsocarriedaPassiveAcousticListeningDevice(PAL)at175+19=194m.PALs can be used to monitor wind speed, rain, marine mammals, and other ambient noisesignals.ThesedataareavailablefromthePIs,Dr.JeffNystuen(UWAPL)andDr.JieYang*(UWAPL).*Dr.JieYanghastakenoverthePALprogramatUWAPL.


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FigureC1:SubsurfacemooringdiagramnearOceanStationPapa.


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ADCPDataThehighestresolutiondataavailable fromthePA001subsurfacemooringwashourly. FigureC2showsUandVvelocitydatafromtheentiredeployment.Thediagonalfeaturecrossingthecenterof theplot is theADCPresolvingtheseasonalchange inmixed layerdepth, increasingfrom<30minSeptemberto~120minFebruary.

FigureC2:PapaNorthPacific(PAPANP)subsurfaceADCPdeploymentneartheOCSPapamooring.

data acquisition and processing report for pa001€¦ · data acquisition and processing report for...

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