V7 MOPITT Level 2 Parameter Table

DIMENSIONS

Dimension NameDefinitionSize
nTimeNumber of retrievalsVaries with each granule
nChanNumber of channels of the instrument8
nTwoFor data fields which include associated variability/uncertainty, first element is the parameter and second element is variability/uncertainty, unless otherwise specified.2
nPrsNumber of pressure levels9
nPrs2Number of pressure levels, including the surface10
nPixThe number of pixels4

GEOLOCATION FIELDS (’HDFEOS/SWATHS/MOP02/Geolocation Fields/…’)

Field NameDefinitionDimensionUnitsData Type*
SecondsinDayTime of the measurement in seconds from the beginning of the day.nTimesF
LatitudeGeolocation of the pixelnTimedegF
LongitudeGeolocation of the pixelnTimedegF
PressurePressure LevelsnPrshPaF
Pressure2Pressure Levels including the surfacenPrs2hPaF
TimeTAI Time of the observationnTimesF

*F = Floating Point I = Integer

RETRIEVED CO (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

Field NameDefinitionDimensionUnitsData Type
RetrrievedCOTotalColumnCO Total ColumnnTwo,nTimemol/cm2F
RetrievedCOMixingRatioProfileCO Mixing Ratio for the layer above each pressure levelnTwo,nPrs,nTimeppbvF
RetrievedCOSurfaceMixingRatioCO Mixing Ratio at the surfacenTwo,nTimeppbvF

A PRIORI FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

Field NameDefinitionDimensionUnitsData Type
APrioriCOMixingRatioProfileTemporally and geographically variable a priori for CO profile based on a climatology for 2000-2009 simulated with the CAM-Chem modelnTwo,nPrs,nTimeppbvF
APrioriCOSurfaceMixingRatioTemporally and geographically variable a priori for surface CO based on a climatology for 2000-2009 simulated with the CAM-Chem modelnTwo,nTimeppbvF
APrioriCOTotalColumnTemporally and geographically variable a priori for total column CO based on a climatology for 2000-2009 simulated with the CAM-Chem modelnTwo,nTimeppbvF

AVERAGING KERNEL FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

These quantities are unitless

Field NameDefinitionDimensionData Type
AveragingKernelRowSumsThis diagnostic provides a single scalar value for each row of the averaging kernel matrix equal to the sum of the elements in that row. Small row-sum values indicate retrieval levels heavily weighted by the a priori while values approaching unity indicate levels with relatively weak sensitivity to the a priori.nPrs2,nTimeF
RetrievalAveragingKernelMatrixFor each retrieval, a floating point array (10 x 10) containing the matrix describing the sensitivity of the retrieved CO profile to the true CO profile. Dimensions of Retrieval Averaging Kernel Matrix are ordered (nrow, ncolumn, ntime)nPrs2,nPrs2,nTimeF
TotalColumnAveragingKernelThis diagnostic allows users to properly compare MOPITT total column retrievals with total columns derived from in-situ profiles or model simulations.Prs2,nTimeF
TotalColumnAveragingKernelDimlessThis diagnostic allows users to properly compare MOPITT total column retrievals with total columns derived from in-situ profiles or model simulations independent of assumed pressure level.nPrs2,nTimeF

CLOUD FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

These quantities are unitless

Field NameDefinitionDimensionData Type
CloudDescription0 = clear, only MOPITT thermal and cloudtop used
1 = clear, only MOPITT thermal used
2 = MOPITT and MODIS cloud mask agree on clear
3 = MODIS cloud mask only clear (when MOPITT determines cloudy)
4 = MOPITT overriding MODIS cloud mask over low clouds (MODIS test flags used)
5 = MODIS cloud mask only, clear over polar regions
6 = Nighttime ocean scenes where the MODIS cloud mask-based test finds that the area was cloudy but MOPITT's thermal-channel radiances finds that the area was clear
7 - 10: reserved for cloud cleared pixels
11 = MOPITT only, cloudy (when MODIS data missing)
12 = First 2 stares in a packet discarded (obsolete for V3)
13 = MOPITT and MODIS cloud mask agree on cloudy
14 = MOPITT clear, MODIS cloudy and failed low cloud tests
15 = MODIS cloud mask only, cloudy over polar regions
nTimeI
MODISCloudDiagnostics(1) Number of "determined" MODIS pixels
(2) Fraction of cloudy MODIS pixels
(3) Fraction of clear MODIS pixels
(4) Average value of "sun glint" MODIS flag
(5) Average value of "snow/ice background" MODIS flag
(6) Average value of "non-cloud obstruction" MODIS flag
(7) Average value of "IR threshold test" MODIS flag
(8) Average value of "IR temperature difference tests" MODIS flag
(9) Average value of "visible reflectance test" MODIS flag
(10) Fraction of "determined" MODIS pixels
10,nTimeF

SURFACE PROPERTY FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

Field NameDefinitionDimensionUnitsData Type
APrioriSurfaceEmissivityFirst guess of surface emissivity from static mapnTwo,nTimeF
APrioriSurfaceTemperatureFirst guess of surface temperature from MERRA2 analysisnTwo,nTimeKF
DEMAltitudeDigital Elevation Model surface heightnTimemF
SurfaceIndex0=water
1=land
2=mixed (coastline)
nTimeI
SurfacePressureSurface pressure from MERRA2 analysis nTimehPaF
RetrievedSurfaceEmissivitySurface emissivity from the retrievalnTwo, nTimeF
RetrievedSurfaceTemperatureSurface temperature from the retrieval nTwo,nTimeKF

RADIANCE FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

Field NameDefinitionDimensionUnitsData Type
DailyGainDevThis diagnostic provides the standard deviation of the gain values used to calibrate the radiances for a particular channel and pixel on one day. In this case, nTwo is the Average and Difference signal gains.nTwo,nChan,nPixF
Level1RadiancesandErrorsFirst index of Level 1 Radiances and Errors corresponds to radiances/uncertainties; second index corresponds to channel (in sequence 7A, 3A, 1A, 5A, 7D, 3D, 1D, 5D, 2A, 6A, 2D, 6D).nTwo,12,nTimeW/m2SrF

RETRIEVAL QUALITY FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

These quantities are unitless

Field NameDefinitionDimensionData Type
DegreesofFreedomforSignalFor each retrieval, a floating point value describing the number of pieces of independent information in the retrieval, equal to the trace of the averaging kernel matrix.nTimeF
MeasurementErrorCovarianceMatrixMeasurement error represents the retrieval uncertainty due to uncertainties in the measured radiances (including instrument 'noise'). nPrs2,nPrs2,nTimeF
RetrievalAnomalyDiagnosticThese flags are set to true when particular anomalous conditions are observed, suggesting that the retrievals should either be ignored or used cautiously. The first four flags (i.e., elements 1-4 of the Retrieval Anomaly Diagnostic array) are set to true (i.e., a value of 1) when one of the thermal channel weighting functions exhibits a sign change vertically. Elements 1-4 correspond respectively to the 5A, 5D, 7A, and 7D weighing functions. The fifth flag of the Retrieval Anomaly Diagnostic array is set to true when the retrieval averaging kernel matrix includes at least one negative element on the matrix diagonal.5,nTimeI
RetrievalErrorCovarianceMatrixFor each retrieval, a floating point array (10 x 10) containing the a posteriori covariance matrix in base-10 log(VMR).nPrs2,nPrs2,nTimeF
RetrievalIterationsThe number of iterations before the forward model converged on a retrievalnTimeI
SignalChi2A measure of the retrieval's goodness of fit.nTimeF
SmoothingErrorCovarianceMatrixSmoothing error represents the retrieval uncertainty due to the influence of a priori and the features of the weighting functions.nPrs2,nPrs2,nTimeF
RetrievedCOTotalColumnDiagnosticsThis two-element vector contains both the estimated smoothing error and measurement error contributions to the total retrieval error (in that order). Smoothing error represents the uncertainty in the retrieved total column due to the departure of the actual total column averaging kernel from the ideal total column averaging kernel. Measurement error describes the uncertainty due to errors in the measured radiances.nTwo,nTimeF

ATMOSPHERIC AND OBSERVATIONAL FIELDS (’HDFEOS/SWATHS/MOP02/Data Fields/…’)

Field NameDefinitionDimensionUnitsData Type
PressureGrid900hPa, 800hPa, 700hPa, 600hPa,500hPa, 400hPa, 300hPa, 200hPa, 100hPnPrshPaF
SolarZenithAngleAngle of solar incidence on the pixelnTimedegF
SatelliteZenithAngleViewing angle of the satellite - nadir is 0nTimedegF
SwathIndexFor each retrieval, a three-element integer vector containing the unique 'pixel' (varies from 1 to 4), 'stare' (varies from 1 to 29), and 'track' indices. 29 stares (equivalent to the mirror pivoting out and back) define one track.3,nTimeI
DryAirColumnDry-air atmospheric column to facilitate the computation of the equivalent mixing ratio of CO averaged over the atmospheric columnnTimemol/cm2F
WaterVaporColumnMoist-air atmospheric column to facilitate the computation of the equivalent mixing ratio of CO averaged over the atmospheric columnnTimemol/cm2F

NOTES: Fill Values are -9999

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