cross track infrared sounder (cris) 1b quality flags

Cross-track Infrared Sounder (CrIS) Level1BQualityFlagsDescriptionDocumentUniversityofWisconsin-MadisonSpaceScienceandEngineeringCenter

Version2.0

JoeTaylor,UW-MadisonSSEC

RevisionHistory

DocumentVersion

SoftwareVersion

Date Comment

Draft 2016-02-18 Creationofdocument0.1 Beta3 2016-03-24 Consistent with Beta 3

implementation1.0Draft1 1.0RC 2016-07-10 Updated for proposed V1.0

implementation1.0Draft2 1.0RC 2016-07-22 Added threshold value tables and

updateddependencytrees1.0Draft3 1.0RC 2016-07-25 Addedthresholdvalues1.0Draft4 1.0RC 2016-07-29 Added preliminary threshold

values for “Invalid InstrumentTemperature” and “ExcessThermalDrift”

1.0Draft5 1.0RC 2016-08-01 Removed redundant check of ICTand DS window sizes from L1bQuality Invalid; removed ES MagSpectrum Check; removed MetLaser Quality Flag; added ISADegradedQF.

1.0Draft6 1.0RC1 2016-08-12 Added information on bandspecific inputs and outputs (colorcoded dependency trees); fixederror in rad cal quality flag = 1(degraded) dependency tree;addedl1afilltoradcalqualityflag=2(invalid)dependencytree.

1.0Draft7 1.0RC3 2016-08-24 Upped Excess Thermal DriftThresholdto1.0K

1.0Draft8 1.0RC6 2016-10-15 Removed section with detail ofRDR/SDR/GEO IDPS QFs; addedcaveat on known error in falsepositives for rad_qual and qualflags.

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DocumentVersion

SoftwareVersion

Date Comment

1.0Draft9 1.0RC7 2016-11-07 Updated lunar intrusion info androlling window thresholdinformation. Added CrIS L1Breferencedocuments.

1.0 1.0RC8 2017-03-09 Changed rolling average nominalandthresholdtobeconsistentwithrc8; document reviewed forrelease.

2.0Draft1 2.0.15 2018-01-25 Restructuring of QF fields andvariable(s) for v2; additionof top-level (0,1,2 valued) QC summaryvariables

2.0 2.0.15 2018-02-27 Editorial revisions; Geo QF infoadded

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TableofContents1 Overview........................................................................................................................................................................8

2 ReferenceDocuments...............................................................................................................................................8

3 Top-LevelQualityControlVariables..................................................................................................................9

4 QualityFlagVariables...............................................................................................................................................9

5 CalibrationQualityFlagVariables......................................................................................................................9

5.1 GeoQuality........................................................................................................................................................12

5.2 InvalidInstrumentTemperature.............................................................................................................12

5.3 ExcessThermalDrift.....................................................................................................................................13

5.4 FCEDetected(Reserved).............................................................................................................................13

5.5 FCECorrectionFailed(Reserved)...........................................................................................................14

5.6 NeonCalibrationQuality.............................................................................................................................14

5.7 ISADegraded....................................................................................................................................................14

5.8 BitTrimMismatch..........................................................................................................................................14

5.9 ScanLineMissing8SecSci.........................................................................................................................15

5.10 L1BQuality.....................................................................................................................................................16

5.11 RadiometricCalibrationQuality............................................................................................................18

5.11.1 ICTTemperatureStability...............................................................................................................19

5.11.2 ICTTemperatureConsistency.......................................................................................................20

5.11.3 NumberofValidPRTTemperatures...........................................................................................20

5.11.4 ESImpulseNoiseCount....................................................................................................................20

5.12 SpectralCalibrationQuality....................................................................................................................21

5.13 ImaginaryRadianceAnomaly.................................................................................................................22

5.14 LunarIntrusionDetected.........................................................................................................................22

5.15 L1aESMissing...............................................................................................................................................23

6 GeolocationQualityFlagVariable....................................................................................................................23

6.1 MissingGeolocationInputs........................................................................................................................23

6.2 StaleEarthOrientationData......................................................................................................................24

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7 CaveatsandKnownIssues..................................................................................................................................24

8 L1BtoSDRQualityFlagComparison..............................................................................................................25

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FiguresFigure1:GeoQualitydependencytree.................................................................................................................12

Figure2: L1bQualityFlagdependency tree forL1bQuality=1 (‘Good’,minorquality issuesdetected)....................................................................................................................................................................16

Figure3:L1bQualityFlagdependencytreeforL1bQuality=2(Invalid)...........................................17

Figure4: RadiometricCalibrationQualityFlagdependencytreeforRadCalQuality=1(Good,minorqualityissuesdetected)........................................................................................................................18

Figure5:RadiometricCalibrationQualityFlagdependencytreeforRadCalQuality=2(Invalid).ThisflagconditionisimplementedwithreducedfunctionalityinVersion2.0.........................19

Figure6:SpectralCalibrationQualityFlagdependencytreeforSpectralCalQuality=1(Good,minor quality issues detected). This flag condition is implemented with reducedfunctionalityinVersion2.0...............................................................................................................................21

Figure7:SpectralCalibrationQualityFlagdependencytreeforSpectralCalQuality=2(Invalid).ThisflagconditionisimplementedwithreducedfunctionalityinVersion2.0.........................22

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TablesTable1:L1bQCvaluesanddescription..................................................................................................................9

Table2:cal_qualflagbitassignments;thisbit-encodedvariablecontainsqualityflaginformationthatisdetectorbandindependent.................................................................................................................10

Table3:cal_lw_qualflagbitassignments.............................................................................................................10

Table4:cal_mw_qualflagbitassignments...........................................................................................................10

Table5:cal_sw_qualflagbitassignments.............................................................................................................11

Table6:GeoQualityinputs........................................................................................................................................12

Table7:GeoQualityvaluesanddescription......................................................................................................12

Table8:InvalidInstrumentTemperatureQualityFlagvaluesanddescription.................................13

Table9:Validrangesforinstrumenttemperatures(TBR:ToBeReviewedfornextrelease)....13

Table10:ExcessThermalDriftQualityFlagvaluesanddescription......................................................13

Table11:ExcessThermalDriftThreshold..........................................................................................................13

Table12:FCEDetectedQualityFlagvaluesanddescription......................................................................14

Table13:FCECorrectionFailedQualityFlagvaluesanddescription....................................................14

Table14:NeonCalibrationQualityFlagvaluesanddescription..............................................................14

Table15:ISADegradedQualityFlagvaluesanddescription.....................................................................14

Table16:BitTrimMismatchQualityFlagvaluesanddescription...........................................................15

Table17:ScanLineMissing8SecSciQualityFlagvaluesanddescription..........................................15

Table18:InputstoL1bQualitydependencytree............................................................................................16

Table19:L1bQualityvaluesanddescription...................................................................................................16

Table20:AbsoluteESSpectrumthresholdvaluesandwavenumberranges(notimplementedinv2.0).............................................................................................................................................................................17

Table21:InputstoRadiometricCalibrationQualitydependencytree..................................................18

Table22:RadiometricCalibrationQualityvaluesanddescription.........................................................18

Table23:InputstoSpectralCalibrationQualitydependencytree..........................................................21

Table24:SpectralCalibrationQualityvaluesanddescription..................................................................21

Table25:ImaginaryRadianceAnomalyvaluesanddescription..............................................................22

Table26:ImaginaryRadianceAnomalythresholdvaluesandwavenumberranges......................22

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Table27:LunarIntrusionDetectedQualityFlagvaluesanddescription.............................................23

Table28:L1aESMissingQualityFlagvaluesanddescription...................................................................23

Table29:geo_qualflagbitassignments.................................................................................................................23

Table30:L1BtoSDRqualityflagcomparison,sortedbySDRQualityFlag.........................................25

Table31:L1BtoSDRqualityflagcomparison,sortedbyL1BQualityFlag.........................................27

Table32:L1BgeolocationtoSDRqualityflagcomparison..........................................................................28

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1 Overview

ThisdocumentdescribesthequalityinformationcontainedintheVersion2.0NASACrISLevel1B(L1B)product.ItisintendedtosupplementthemoregeneraldescriptionoftheproductthatisfoundintheCrISL1BProductUsers’Guide,Version2.0.

Qualityinformationincludestop-levelQualityControlvariablesaswellasQualityFlagvariables.

2 ReferenceDocuments

1. CrISL1BProductUsers’Guide,Version2.02. NASASNPPCrossTrackInfraredSounder(CrIS)Level1BDeltaAlgorithmTheoreticalBasis

Document(ATBD),Version2.03. CrISL1BSoftwareUsers’Guide,Version2.04. CrossTrack Infrared Sounder (CrIS) SensorDataRecord (SDR)User’s Guide, Version 1.0,

NOAATechnicalReportNESDIS1435. JointPolarSatelliteSystem(JPSS)OperationalAlgorithmDescription(OAD)Document for

Cross-track Infrared Sounder (CrIS) SensorDataRecord (SDR) Software,RevisionF, JointPolarSatelliteSystem(JPSS)GroundProjectCode474474-00071

6. JointPolarSatelliteSystem(JPSS)AlgorithmSpecificationVolumeI:SoftwareRequirementSpecification (SRS) for the CrIS RDR/SDR, Block 2.0.0, Joint Polar Satellite System (JPSS)GroundProjectCode474474-00448-01-03-B0200

7. JointPolarSatelliteSystem(JPSS)AlgorithmSpecificationVolumeII:DataDictionaryfortheCrISRDR/SDR,Block2.0.0,JointPolarSatelliteSystem(JPSS)GroundProjectCode474474-00448-02-03-B0200

8. JointPolarSatelliteSystem(JPSS)CrossTrackInfraredSounder(CrIS)SensorDataRecords(SDR) Algorithm Theoretical Basis Document (ATBD), Revision C, Joint Polar SatelliteSystem(JPSS)GroundProjectCode474474-00032

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3 Top-LevelQualityControlVariables

Forthev2.0release,threetop-levelQualityControl(QC)variableshavebeenadded(rad_lw_qc,rad_mw_qc,rad_sw_qc).Thesevariablesarevalued0,1,or2andsummarizethequalityofthecalibratedradianceproductforeachdetectorband,withonevalueperobservation.

Table1:L1bQCvaluesanddescription.

0 NoL1Bqualityissues1 L1Bquality‘Good’.Minorqualityissuesdetected,productmaybeslightlydegradedbut

islikelyofacceptablequalitytoendusers.RefertoL1a,geo,L1bqualityflagsformoreinformation

2 L1Bquality‘Invalid’.RefertoL1a,geo,L1bqualityflagsformoreinformation

The values in each QC variable are obtained directly from the L1B summary flag in thecalibration quality flag variable for the corresponding band. For information on how thosevaluesaredetermined,refertoSection5.10L1BQuality.

4 QualityFlagVariables

QualityFlag(QF)variablesarebit-fieldsprovidinginformationonspecificissuesthataffectthecalibrationorgeolocationquality.

TheindividualflagsthatmakeupQFvariablescanbebrokenoutbyapplyingbit-masks.Theseflagsmaybeoneormorebitsinlength.Foreachflag,avalueof0indicatesnoissues,andanon-zerovalueindicatesissueswereencountered.

Userswhoarenotinterestedinbreakingoutindividualflagstogetdetailedinformationaboutspecific issues should use the top-level Quality Control variables described in Section 3.Alternatively,theycantreatthequalityflagvariablesasintegers,whereavalueof0indicatesnoissueswereencountered,andanon-zerovalueindicatesissueswereencountered.

TheQualityFlagvariablesandtheirderivationaredescribedinthefollowingsections.NotethattheflagsandtheirmeaningsarealsofullydescribedbyvariableattributesincompliancewiththeClimateandForecast(CF)standard.ForinformationonusingtheseattributestointerpretQFvalues,refertotheCFdocumentation.

5 CalibrationQualityFlagVariables

Forthev2.0release,theL1bcalibrationqualityflagshavebeenregroupedfromasingle64-bitbit-encodedvariabletofour32-bitbit-encodedvariables(Table2-Table5). Thecal_qualflagvariable contains quality flag information that is detector band independent. Thecal_lw_qualflag, cal_mw_qualflag, and cal_sw_qualflag contain quality flag information that isdetector band dependent, and each of these 3 variables have identical bit encoding and

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information format for the LW,MW, and SW bands, respectively. No new quality flags havebeenaddedforv2.0,buttheQFlogichasbeenadjustedwherenecessaryforthechangeinthedefinitionofaQFvalueof1to‘good’from‘degraded’for{0,1,2}valuedQFs.

Table 2: cal_qualflag bit assignments; this bit-encoded variable contains quality flag information that isdetectorbandindependent.

Name BitAssignment InitialRelease SectionGeoQuality B0 Version1 Section5.1InvalidInstrumentTemperature B1 Version1 Section5.2ExcessThermalDrift B2 Version1 Section5.3FCEDetected(Reserved) B3 Section5.4FCECorrectionFailed(Reserved) B4 Section5.5NeonCalibrationQuality B5 Version1 Section5.6ISADegraded B6 Version1 Section5.7BitTrimMismatch* B7 Beta3 Section5.8ScanLineMissing8SecSci* B8 Beta3 Section5.9Unassigned B9-31

Table3:cal_lw_qualflagbitassignments.

Name BitAssignment InitialRelease SectionLWL1BQuality B0–B1 Beta3 Section5.10LWRadiometricCalibrationQuality B2–B3 Version1 Section5.11LWSpectralCalibrationQuality B4–B5 Version1 Section5.12LWImaginaryRadianceAnomaly B6 Beta3 Section5.13LWLunarIntrusionDetected B7 Version1 Section5.14LWL1aESMissing* B8 Beta3 Section5.15Unassigned B9-31 *replicatedfromES/l1a_qual

Table4:cal_mw_qualflagbitassignments.

Name BitAssignment InitialRelease SectionMWL1BQuality B0–B1 Beta3 Section5.10MWRadiometricCalibrationQuality B2–B3 Version1 Section5.11MWSpectralCalibrationQuality B4–B5 Version1 Section5.12MWImaginaryRadianceAnomaly B6 Beta3 Section5.13MWLunarIntrusionDetected B7 Version1 Section5.14MWL1aESMissing* B8 Beta3 Section5.15Unassigned B9-31 *replicatedfromES/l1a_qual

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Table5:cal_sw_qualflagbitassignments.

Name BitAssignment InitialRelease SectionSWL1BQuality B0–B1 Beta3 Section5.10SWRadiometricCalibrationQuality B2–B3 Version1 Section5.11SWSpectralCalibrationQuality B4–B5 Version1 Section5.12SWImaginaryRadianceAnomaly B6 Beta3 Section5.13SWLunarIntrusionDetected B7 Version1 Section5.14SWL1aESMissing* B8 Beta3 Section5.15Unassigned B9-31 *replicatedfromES/l1a_qual

Thefollowingsectionsdescribethemeaningsoftheindividualflagsthatmakeupthecalibrationqualityflagvariables.

Forflagsthataresetbasedonmultipleinputs,thecriteriaforpromotingfromthedefaultvalueof0(noissues)tosuccessivelylargervaluesareshownindependencytreelogicdiagrams.

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5.1 GeoQualityThis is a summary flag of the overall geolocation quality with value range 0 – 1. The bitassignmentwithincal_qualflagisdefinedinTable2.

Table6:GeoQualityinputs.

Input InputType Reference Version2obs-time-missing QualityFlag GeoQF Yesservo-errors-missing QualityFlag GeoQF Yesspacecraft-diary-missing QualityFlag GeoQF Yesstale-utcpole QualityFlag GeoQF Yes

Table7:GeoQualityvaluesanddescription.

Value Description0 Nogeolocationqualityissues1 Geolocationqualityissues.Refertogeo_qualflagformoreinformation.

Figure1:GeoQualitydependencytree.

5.2 InvalidInstrumentTemperatureThe Invalid Instrument Temperature flag is intended to identify the situation when themeasured temperaturesof certain instrument componentsareoutof allowable ranges.Thesetemperature measurements are used to compute the contributions of the instrumentcomponentstotheICTradiometricmodel.Thisflaghasarangeof0–1,andthecal_qualflagbitassignmentisdefinedinTable2.

OR

geo_qualflag:obs-time-missing

geo_qualflag:servo-errors-missing

Geo Quality = 1

geo_qualflag:spacecraft-diary-missing >= 1

geo_qualflag:stale-utcpole

OR

OR

Black Text / Lines: Version 2 implementationGrey Text / Lines: Possible future implementation

Grey Fill: Band Dependent (LW, MW, SW)

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Table8:InvalidInstrumentTemperatureQualityFlagvaluesanddescription.

Value Description0 Allinstrumenttemperatureswithinrespectivethresholds1 Instrumenttemperatureoutsideofrespectivethreshold

Table9:Validrangesforinstrumenttemperatures(TBR:ToBeReviewedfornextrelease).

Temperature MinValue MaxValueT_PRT1 270(TBR) 290(TBR)T_PRT2 270(TBR) 290(TBR)OMA_structure_input_1 270(TBR) 290(TBR)OMA_structure_input_2 270(TBR) 290(TBR)SSM_scan_mirror 270(TBR) 290(TBR)beamsplitter_1 270(TBR) 290(TBR)SSM_scan_mirror_baffle 270(TBR) 290(TBR)

5.3 ExcessThermalDriftThe Excess Thermal Drift flag is intended to identify the situation when the measuredtemperatureofanyinstrumentcomponentshasdriftedgreaterthantheallowablelimitwithinthe period of a single granule. These temperature measurements are used to compute thecontributionsoftheinstrumentcomponentstotheICTradiometricmodel.Thisflaghasarangeof0–1,andthecal_qualflagbitassignmentisdefinedinTable2.

Table10:ExcessThermalDriftQualityFlagvaluesanddescription.

Value Description0 Noexcessthermaldriftofinstrumenttemperatures1 Thermaldriftbetweenmeasurementsexceedsrespectivethreshold

Table11:ExcessThermalDriftThreshold.

Temperature ThresholdT_PRT1 +/-1.0(TBR)T_PRT2 +/-1.0(TBR)OMA_structure_input_1 +/-1.0(TBR)OMA_structure_input_2 +/-1.0(TBR)SSM_scan_mirror +/-1.0(TBR)beamsplitter_1 +/-1.0(TBR)SSM_scan_mirror_baffle +/-1.0(TBR)

5.4 FCEDetected(Reserved)The FCE (Fringe Count Error) Detected flag has a range of 0 – 1, and the cal_qualflag bitassignmentisdefinedinTable2. ThisflagisnotimplementedfortheVersion2.0releaseandwillalwaysbesetto0.

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Table12:FCEDetectedQualityFlagvaluesanddescription.

Value Description0 Nofringecounterrordetected1 Fringecounterrordetected

5.5 FCECorrectionFailed(Reserved)Thisflaghasarangeof0–1,andthecal_qualflagbitassignmentisdefinedinTable2.ThisflagisnotimplementedfortheVersion2.0releaseandwillalwaysbesetto0.

Table13:FCECorrectionFailedQualityFlagvaluesanddescription.

Value Description0 FCEcorrectionsuccessful1 FCEcorrectionfailed

5.6 NeonCalibrationQualityThisflaghasarangeof0–1,andthecal_qualflagbitassignmentisdefinedinTable2.

Table14:NeonCalibrationQualityFlagvaluesanddescription.

Value Description0 Lessthan25%oftheneoncalibrationdatasetvariedfromthemeanbygreaterthanthe

28ppmthreshold1 25%orgreateroftheneoncalibrationdatasetvariedfromthemeanbygreaterthanthe

28ppmthreshold

5.7 ISADegradedThe ISADegraded flag is intended to identify the situationwhen the inverse self-apodizationmatricesthatareusedintheself-apodizationcorrectionweregeneratedforametrologylaserwavenumber that differs from the currentmetrology laserwavenumber bymore than a pre-definedthreshold(15ppm).Thisflaghasarangeof0–1,andthecal_qualflagbitassignmentisdefinedinTable2.

Table15:ISADegradedQualityFlagvaluesanddescription.

Value Description0 Current laserwavenumbervaluediffersby less than15ppmwithrespect tothe laser

wavenumberusedtocalculatetheISAmatrices1 Currentlaserwavenumbervaluediffersby15ppmorgreaterwithrespecttothelaser

wavenumberusedtocalculatetheISAmatrices

5.8 BitTrimMismatchThis flaghasarangeof0–1, ispropagated fromthecorrespondingES/l1a_qual flag,andthecal_qualflagbitassignmentisdefinedinTable2.

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Table16:BitTrimMismatchQualityFlagvaluesanddescription.

Value Description0 Bittrimsucceeded1 Bittrimfailed,toomuchortoolittlepackedinterferogramdata

5.9 ScanLineMissing8SecSciThis flaghasarangeof0–1, ispropagated fromthecorrespondingES/l1a_qual flag,andthecal_qualflagbitassignmentisdefinedinTable2.

Table17:ScanLineMissing8SecSciQualityFlagvaluesanddescription.

Value Description0 8-secsciencepacketavailableforthisscanline1 8-secsciencepacketunavailableforthisscanline

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5.10 L1BQualityThese are summary flags (LW,MW, SW)with value range 0 – 2. The dependency trees areshowninFigure2(L1BQuality=1)andFigure3(L1BQuality=2),withtheinputssummarizedin Table 18. L1b Quality Flag Values are summarized in Table 19 and band-specific QF bitassignments aredefined inTable3, Table4, andTable5. The top-levelQualityControl (QC)variablesdescribedinSection3aresetdirectlyfromtheL1bQualityFlags(LW,MW,SW).

Table18:InputstoL1bQualitydependencytree.

Input InputType Reference Version2RadiometricCalibrationQuality QualityFlag Section5.11 YesSpectralCalibrationQuality QualityFlag Section5.12 YesGeoQuality QualityFlag Section5.1 YesBitTrimMismatch QualityFlag L1aQF YesScanLineMissing8SecSci QualityFlag L1aQF YesL1aESMissing QualityFlag L1aQF YesImaginaryRadianceAnomaly QualityFlag Section5.13 YesESSpectrum Value(testvs.threshold) Table20 NO(TBR)

Table19:L1bQualityvaluesanddescription.

Value Description0 NoL1Bqualityissues1 L1Bquality‘Good’(minorqualityissuesdetected).RefertoL1a,geo,L1bqualityflags

formoreinformation2 L1Bquality‘Invalid’.RefertoL1a,geo,L1bqualityflagsformoreinformation

Figure2:L1bQualityFlagdependencytreeforL1bQuality=1(‘Good’,minorqualityissuesdetected).

OR

Radiometric Calibration Quality = 1 (Good)

Spectral Calibration Quality = 1 (Good)

Geo Quality = 1 (Invalid)OR

L1b Quality = 1 (Good)



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Figure3:L1bQualityFlagdependencytreeforL1bQuality=2(Invalid).

Table20:AbsoluteESSpectrumthresholdvaluesandwavenumberranges(notimplementedinv2.0).

Band WavenumberRangeforthresholdcheck ThresholdValueMin(cm-1) Max(cm-1)

LW 779(TBR) 960(TBR) TBDMW 1455(TBR) 1655(TBR) TBDSW 2230(TBR) 2330(TBR) TBD

OR

Radiometric Calibration Quality = 2 (Invalid)

Spectral Calibration Quality = 2 (Invalid)

Bit Trim = 1 (Failed)

OR

L1b Quality = 2 (Invalid)

Scan Line Missing 8 Sec Sci = 1

OR

ES Data Missing = 1

OR

Imaginary RadianceAnomaly = 1

OR

⎮ES Spectrum⎮ > ThresholdBlack Text / Lines: Version 2 implementation

Grey Text / Lines: Possible future implementationGrey Fill: Band Dependent (LW, MW, SW)

L1a Fill = 1

OR

OR

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5.11 RadiometricCalibrationQualityThesearesummaryflagsdescribingtheoverallradiometriccalibrationquality(LW,MW,SW)withvaluerange0–2. ThedependencytreesareshowninFigure4(RadiometricCalibrationQuality=1)andFigure5(RadiometricCalibrationQuality=2),withtheinputssummarizedinTable 21. Radiometric Calibration Quality Flag values are summarized in Table 22, and theband-specificQFbitassignmentsaredefinedinTable3,Table4,andTable5. TheseflagsareimplementedatreducedfunctionalityfortheVersion2.0release.

Table21:InputstoRadiometricCalibrationQualitydependencytree.

Input InputType Reference Version2DSWindowSize(WS) Value(testvs.threshold)

0:24<=DSWS<291:19<DSWS<24

Figure4Figure5

Yes

ICTWindowSize(WS) Value(testvs.threshold)0:24<=DSWS<291:19<DSWS<24

Figure4Figure5

Yes

ICTTemperatureStability Value(testvs.threshold) Section5.11.1

Yes

ICTTemperatureConsistency Value(testvs.threshold) Section5.11.2

Yes

NumberofValidPRTTemperatures Value(testvs.threshold) Section5.11.3

Yes(TBR)

ESImpulseNoiseCount Value(testvs.threshold) No(TBR)ExcessThermalDrift QualityFlag Section5.3 YesInvalidInstrumentTemperature QualityFlag Section5.2 Yes

Table22:RadiometricCalibrationQualityvaluesanddescription.

Value Description0 Noqualityissuesdetected1 ‘Good’radiometriccalibration(minorqualityissuesdetected)2 Invalidradiometriccalibration

Figure4:RadiometricCalibrationQualityFlagdependencytreeforRadCalQuality=1(Good,minorqualityissuesdetected).

OR

19 < DS Window Size <24

19 < ICT Window Size <24

Radiometric Calibration Quality = 1 (Good)



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Figure5: RadiometricCalibrationQualityFlagdependencytreeforRadCalQuality=2(Invalid). ThisflagconditionisimplementedwithreducedfunctionalityinVersion2.0.

5.11.1 ICTTemperatureStability

ThresholdValue: 1.0(TBR)ictTempStabilityThreshold

FromtheSDRUser’sGuide[REF1]:

ICT_TemperatureStabilitymeasuresthestabilityofthetwoPRTmeasurementsoftheICT.Thisvariableiscalculatedusingthefollowingequation:

ICTTS = T i( )− 1ICTWS

T j( )j=1

ICTWS

∑⎡

⎣⎢

⎤

⎦⎥

i=1

ICTWS

∑2

ICTWS −1( ) (1.1)

OR

DS Window Size <= 19

ICT Window Size <= 19

Radiometric Calibration Quality = 2 (Invalid)



ICT Temperature Stability > Threshold

OR

ICT Temperature Consistency > Threshold

0 < Number of Valid PRT Temperatures < Threshold

OR

ES Impulse Noise Count > Threshold

OR

Excess Thermal Drift = 1

OR

OR

Invalid Instrument Temperature = 1

OR

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whereICTWSistheICTWindowSize,T i( ) = 1N

T i,k( )k=1

N

∑ T i( ) = 1N

T i,k( )k=1

N

∑ ,whereT(i,k)

is the convertedPRT temperature in thevalidatedkth epoch, represents theaverage ICTtemperaturemeasured fromaPRTforthe ith scan.Thisvariable issetseparately forthetwoPRTs.

5.11.2 ICTTemperatureConsistency

ThresholdValue: 1.0(TBR)ictTempConsistencyThreshold


ICT_TemperatureConsistency measures the consistency between the two PRTmeasurementsoftheICT.Thisvariableiscalculatedusingthefollowingequation:

ICTTC = 1ICTWS

T1 i( )i=1

ICTWS

∑ − 1ICTWS

T2 i( )i=1

ICTWS

∑ (1.2)

The nomenclature is similar to the ICT_TemperatureStability variable except that thesubscripts1and2denotethetwoPRTs,respectively.

5.11.3 NumberofValidPRTTemperatures

ThethresholdvaluefromtheIDPS/ADLconfiguration(PCT)binaryfileisnotedbelow.

ThresholdValue: 15(numOfValidPRTTempThreshold)


numberOfValidPRTTemperatures represents the number of PRT temperatures that havebeenvalidatedusingtheproceduredescribedbelow.Themeanandstandarddeviationofthe PRT temperatures is calculated to identify any outliers, which are defined as beingdifferent from themean by an amount ofmore than 3-sigma (standard deviation). Theoutliersdonotentersubsequentprocessing.

5.11.4 ESImpulseNoiseCountThe threshold value from the IDPS/ADL configuration (PCT) binary file is notedbelow. ThistestisnotimplementedfortheVersion2.0release.

ThresholdValue: 2(impulseNoiseCountThreshold)

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5.12 SpectralCalibrationQualityThesearesummaryflags(LW,MW,SW)describingtheoverallspectralcalibrationqualitywithvalue range 0 – 2 where the dependency trees are shown in Figure 6 (Spectral CalibrationQuality = 1) and Figure 7 (Spectral Calibration Quality = 2), with the inputs summarized inTable 23. Quality Flag values are summarized in Table 24, and the band-specific QF bitassignments are defined in Table 3, Table 4, and Table 5. These flags are implemented at areducedfunctionalityfortheVersion2.0release.Theusageof“FCEDetected”,“FCECorrectionFailed”,and“MetLaserMonitored”hasbeenomittedfromv2.0.

Table23:InputstoSpectralCalibrationQualitydependencytree.

Input InputType Reference Version2FCEDetected QualityFlag Section5.4 NOFCECorrectionFailed QualityFlag Section5.5 NONeonCalibrationQuality QualityFlag Section5.6 YesISADegraded QualityFlag Section5.7 YesMetLaserMonitored TBD NO

Table24:SpectralCalibrationQualityvaluesanddescription.

Value Description0 Noqualityissuesdetected1 ‘Good’spectralcalibration(minorqualityissuesdetected)2 Invalidspectralcalibration

Figure6:SpectralCalibrationQualityFlagdependencytreeforSpectralCalQuality=1(Good,minorqualityissuesdetected).ThisflagconditionisimplementedwithreducedfunctionalityinVersion2.0.

Neon Calibration Quality = 1

Spectral Calibration Quality = 1 (Good)

ISA Degraded = 0

AND



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Figure7: SpectralCalibrationQualityFlagdependencytreeforSpectralCalQuality=2(Invalid). ThisflagconditionisimplementedwithreducedfunctionalityinVersion2.0.

5.13 ImaginaryRadianceAnomalyAlarge imaginarycomponentof thecalibratedradiance isan indicationofpoorqualityof thecalibratedradiance. Theseflags(LW,MW,SW)indicatewhetherthe imaginarycomponentofthecalibratedradianceexceedsthedefinedthresholds,withvaluerange0–1.Band-specificQFbitassignmentsaredefinedinTable3,Table4,andTable5.

Table25:ImaginaryRadianceAnomalyvaluesanddescription.

Value Description0 Imaginarycomponentofthecalibratedradianceiswithinthethresholdvalue1 Imaginarycomponentofthecalibratedradianceexceedsthethresholdvalue

Table26:ImaginaryRadianceAnomalythresholdvaluesandwavenumberranges.

Band WavenumberRangeforthresholdcheck ThresholdValueMin(Index) Max(Index)

LW 779 960 +/-1.5MW 1455 1655 +/-0.88*SW 2230 2330 +/-0.05***multipliedbysqrt(2)forFSRdata**multipliedby2forFSRdata

5.14 LunarIntrusionDetectedTheLunarIntrusionDetectedflagsindicatethatalunarintrusionhasbeendetectedinthedeepspacereferencespectrawithinthemovingaveragewindowspan.Iflunarintrusionisdetected,the DS spectrum is marked as invalid and excluded from the moving window average. ThisresultsinareducednumberofDSspectraintheslidingwindowaverageusedinthecalibrationof the current observation. These flags have a range of 0 – 1, and the band-specific QF bitassignmentisdefinedinTable3.

OR

FCE Correction Failed = 1

Neon Calibration Quality = 1

Spectral Calibration Quality = 2 (Invalid)

ISA Degraded = 1

AND



23

Table27:LunarIntrusionDetectedQualityFlagvaluesanddescription.

Value Description0 NoDSviewsaffectedbylunarintrusion1 AtleastoneDSviewisaffectedbymoonwithinthemovingwindow

5.15 L1aESMissingThis flaghasarangeof0–1, ispropagated fromthecorrespondingES/l1a_qual flag,andtheband-specificQFbitassignmentisdefinedinTable3.

Table28:L1aESMissingQualityFlagvaluesanddescription.

Value Description0 CompleteESinterferogrampacket1 Interferogrampacketwasnotreceived

6 GeolocationQualityFlagVariableThegeo_qualflagvariablecontainsqualityinformationregardingthecalculationofobservationearth locationand related fields.Table29: geo_qualflagbit assignments and the sections thatfollowprovideasummaryofthegeo_qualflagfieldsandtheirmeanings.

Table29:geo_qualflagbitassignments.

Name BitAssignment InitialRelease ReferenceObservationTimeMissing B0 Version1 Section6.1ServoErrorMissing B1 Version1 Section6.1SpacecraftDiaryGap B2-B3 Version1 Section6.1StaleEarthOrientationData B4 Version1 Section6.2

6.1 MissingGeolocationInputsThe first three fields inTable29:geo_qualflagbitassignmentssignal that inputdata fromtheinstrumentdatastreamessentialtogeolocationisunavailable.

Observation times and scan mirror servo error angles (along- and across-track) must beprovidedforeveryobservationforgeolocationtosucceed.

Spacecraft diary refers to spacecraft position, velocity, and attitude information which isavailableoncepersecondintheinstrumentdataandinterpolatedtotheobservationtimesbythe geolocation software. The Spacecraft Diary Gap field can be set to one of three nonzerovalues to indicate missing diary information. Binary values 01, 10, and 11 are used torespectively signify small, medium, or large gaps. All versions of the geolocation modulereleasedthusfarmarkallgapsassmall,butthismaychangeinafuturerelease.

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6.2 StaleEarthOrientationDataTheCrISL1Bgeolocationsoftwarerequiresanancillaryfilecontainingearthrotationangleandpolarmotionvaluestabulatedovertime.Thecorrespondingbitingeo_qualflagwillbesetifthisfiledoesnothavedatacoveringthetimeofobservation.

7 CaveatsandKnownIssuesFurther refinement of the lunar intrusion check algorithm is still desirable. The currentalgorithm is based on the IDPS method but has been modified to account for the issuesidentifiedinthatmethod,andincorporatestighterthresholdsinv2.0.15thanusedintheIDPSsoftware.

TheLW,MW,andSWL1bQualityFlags(andcorrespondingQCvariablesrad_lw_qc,rad_mw_qc,rad_sw_qc)arecurrentlyset toavalueof1(‘Good’),whentheRadCalQualityFlag isset to1(Good),ORSpectralCalQualityFlagissetto1(Good),ORGeoQualityFlagissetto1(InvalidGeo).Forfuturereleasesthislogicshouldbereviewedasitisnotclearthataradianceshouldbe considered to be ‘Good’without good geolocation. It is expected that there are very fewinstanceswhere theRadCalQualityFlagand/or theSpectralCalQualityFlagwillbe set to1(Good)whiletheGeoQualityFlagissetto1.

TheGeoQF ‘spacecraft-dairy-missing’ isa2-bitQF(nogap, smallgap,mediumgap, largegapdetected),butonlyusessinglebitfunctionalityinsoftwarereleasev2.0(0=nogapdetectedor1=gapdetected).

A false positive for Imaginary Radiance Anomalymay be indicated for extremely hot scenes.Thresholdvaluesandalgorithmoptimizationwillbereviewedpriortothev3.0release.

SpectralCalibrationQualitycurrentlyissetto1(Good)forthecaseinwhichtheISADegradedflagisclear,buttheNeonCalQualityFlagisset.Itisexpectedthatthereareveryfewinstancesforwhichthiscombinationoccurs,butthislogicaltestwillbereviewedpriortothev3.0release.

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8 L1BtoSDRQualityFlagComparison

Table30:L1BtoSDRqualityflagcomparison,sortedbySDRQualityFlag.

RDR/SDR/GEO L1BQualityFlag QualityVariable

(Bit)QualityFlag(#ofbits) Init

RelDataGap QF1_SCAN_CRISSDR

(B0)LWESMissing(1)*MWESMissing(1)*SWESMissing(1)*

B3

TimingSequenceError

QF1_SCAN_CRISSDR(B1)

NotimplementedinV2.0

LambdaMonitoredQuality



InvalidInstrumentTemperature


InvalidInstrumentTemperature(1) V1

ExcessThermalDrift


ExcessThermalDrift(1) V1

SuspectNeonCalibration


NeonCalibrationQuality(1) V1

LunarIntrusionForward

QF2_CRISSDR(B0)

LWLunarIntrusionDetected(1)MWLunarIntrusionDetected(1)SWLunarIntrusionDetected(1)

V1

LunarIntrusionReverse

QF2_CRISSDR(B1)

SDROverallQuality QF3_CRISSDR(B0-B1)

LWL1BQuality(2)MWL1BQuality(2)SWL1BQuality(2)

B3

InvalidGeolocation QF3_CRISSDR(B2)

GeoQuality(1)(TBD) B3

InvalidRadiometricCalibration

QF3_CRISSDR(B3-B4)

LWRadiometricCalibrationQuality(2)MWRadiometricCalibrationQuality(2)SWRadiometricCalibrationQuality(2)

V1

InvalidSpectralCalibration

QF3_CRISSDR(B5-B6)

LWSpectralCalibrationQuality(2)MWSpectralCalibrationQuality(2)SWSpectralCalibrationQuality(2)

V1

SDRFCECorrectionFailed

QF3_CRISSDR(B7)

FCECorrectionFailed(1)NotimplementedinV2.0

Day/NightIndicator QF4_CRISSDR(B0)


InvalidRDR QF4_CRISSDR(B1)

N/A

FCEDetected QF4_CRISSDR(B2)

FCEDetected(1)NotimplementedinV2.0

BitTrimFailed QF4_CRISSDR(B3)

BitTrim(1)* B3

ImaginaryRadianceAnomaly

QF4_CRISSDR(B4)

LWImaginaryRadianceAnomaly(1)MWImaginaryRadianceAnomaly(1)

B3

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SWImaginaryRadianceAnomaly(1)AttitudeandEphemerisavailability

QF1_CRISSDRGEO(B0-B1)

SpacecraftDiaryGap(2)** V1

ScanLineMissing8SecSci(1)* B3 ISADegraded(1) V1 ObservationTimeMissing(1)** V1 ServoErrorsMissing(1)** V1 StaleEarthOrientationData(1)** V1*replicatedfromES/l1a_qual**geolocationflag(ingeo_qualflagvariable)

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Table31:L1BtoSDRqualityflagcomparison,sortedbyL1BQualityFlag.

L1B RDR/SDR/GEOQualityFlag(#ofbits) Init

RelQualityFlag QualityVariable

(BitAddress)GeoQuality(1) Beta

3InvalidGeolocation QF3_CRISSDR

(B2)InvalidInstrumentTemperature(1) V1 InvalidInstrument

TemperatureQF1_SCAN_CRISSDR(B3)

ExcessThermalDrift(1) V1 ExcessThermalDrift


FCEDetected(1)NotimplementedinV2.0

FCEDetected QF4_CRISSDR(B2)

FCECorrectionFailed(1)NotimplementedinV2.0

SDRFCECorrectionFailed

QF3_CRISSDR(B7)

NeonCalibrationQuality(1) V1 SuspectNeonCalibration


ISADegraded(1) V1 N/A N/ABitTrim(1)* Beta

3BitTrimFailed QF4_CRISSDR

(B3)ScanLineMissing8SecSci(1)* Beta

3

LWL1BQuality(2)MWL1BQuality(2)SWL1BQuality(2)

Beta3

SDROverallQuality QF3_CRISSDR(B0-B1)

LWRadiometricCalibrationQuality(2)MWRadiometricCalibrationQuality(2)SWRadiometricCalibrationQuality(2)

V1 InvalidRadiometricCalibration

QF3_CRISSDR(B3-B4)

LWSpectralCalibrationQuality(2)MWSpectralCalibrationQuality(2)SWSpectralCalibrationQuality(2)

V1 InvalidSpectralCalibration

QF3_CRISSDR(B5-B6)

LWImaginaryRadianceAnomaly(1)MWImaginaryRadianceAnomaly(1)SWImaginaryRadianceAnomaly(1)

Beta3

ImaginaryRadianceAnomaly

QF4_CRISSDR(B4)

LWLunarIntrusionDetected(1)MWLunarIntrusionDetected(1)SWLunarIntrusionDetected(1)

V1 LunarIntrusionForward

QF2_CRISSDR(B0)

LunarIntrusionReverse

QF2_CRISSDR(B1)

NotimplementedinV2.0 LambdaMonitoredQuality


NotimplementedinV2.0 TimingSequenceError


LWESMissing(1)*MWESMissing(1)*SWESMissing(1)*

Beta3

DataGap QF1_SCAN_CRISSDR(B0)

N/A InvalidRDR QF4_CRISSDR(B1)

NotimplementedinV2.0 Day/NightIndicator QF4_CRISSDR(B0)

*replicatedfromES/l1a_qual

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Table32:L1BgeolocationtoSDRqualityflagcomparison.

L1B RDR/SDR/GEOQualityFlag(#ofbits) Init

RelQualityFlag QualityVariable

(BitAddress)ObservationTimeMissing(1) V1 N/A N/AServoErrorsMissing(1) V1 N/A N/ASpacecraftDiaryGap(2) V1 Attitudeand

Ephemerisavailability

QF1_CRISSDRGEO(B0-B1)

StaleEarthOrientationData(1) V1 N/A N/A