TOVS Pathfinder Path-P Daily and Monthly Polar Gridded Atmospheric Parameters

Appendix A: Data Dictionary

The data dictionary in this section describes the elements associated with the two Scientific Data Set (SDS) objects contained in the TOVS Path-P files. The first SDS object is Global Attributes which defines attributes that describe an individual Path-P file and contains information common to all of the data set arrays in the file. The other SDS object is Scientific Data Sets which describes the individual scientific data arrays and their associated metadata.

The attributes that comprise the Global Attributes object are defined by the following elements:


 Element

  Parameter Name       = PROJECT
  Definition           = Name of project
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Current Value is "TOVS PATHFINDER PATHP"


 Element

  Parameter Name       = DATASET_NAME
  Definition           = Producer's name of data set
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Possible values for this project are
                         "Gridded Daily Arctic Atmospheric Data from TOVS(PathP)"
                         "Gridded Monthly Arctic Atmospheric Data from TOVS(PathP)"

 Element

  Parameter Name       = SOURCE_NAME
  Definition           = Satellite Platform
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                = NOAA-10
  Comment              =


  
 Element

  Parameter Name       = PROCESSING_LEVEL
  Definition           = Level of Processing Number
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Value is "3"

 
 Element

  Parameter Name       = REFERENCE_DATE
  Definition           = Date or time period for which this granule is 
                         representative
  Format               = yyyy-mm-dd
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              =


 Element

  Parameter Name       = START_DATE
  Definition           = Date and time of first datapoint in granule
  Format               = yyyy-mm-ddTHH:MM:SS
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Example of this attribute is "1987-10-01T01:41:51"


 Element

  Parameter Name       = STOP_DATE
  Definition           = Date and time of last datapoint in granule
  Format               = yyyy-mm-ddTHH:MM:SS
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Example of this attribute is "1987-10-01T22:41:51"


 Element

  Parameter Name       = POSITION_TYPE
  Definition           = A type of spatial object defined in the NSIDC IMS 
                         Server 
  Format               =
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Value of this attribute is "FIXED GRID"


 Element

  Parameter Name       = GRID_TYPE
  Definition           = Northern or Southern Hemisphere
  Format               =
  Type                 = character
  Length               = 1
  Range                =
  Comment              = Possible values are "N" or "S"


 Element

  Parameter Name       = GRID_NAME
  Definition           = Name of Grid
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Value for this attribute is "EASE GRID"


 Element

  Parameter Name       = PROJECTION
  Definition           = Geographical projection of the grid
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = Value for this attribute is "Azimuthal Equal Area"


 Element

  Parameter Name       = EASE_GRD
  Definition           = Grid parameter file used by NSIDC gridding software
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = This file defines the parameters required by the 
                         gridding software developed by NSIDC.
 

 Element

  Parameter Name       = EASE_MPP
  Definition           = Map projection parameter file used by NSIDC 
                         projection software
  Format               = string
  Type                 = character
  Length               = Max 256
  Range                =
  Comment              = This file defines the parameters of the EASE-Grid 
                         map projection required by the projection software
                         developed by NSIDC. 


 Element

  Parameter Name       = LATITUDE
  Definition           = Latitude of the corner points of the grid
  Format               = f6.3
  Type                 = float32
  Length               = 4 * float32 (16 bytes)
  Range                = (-90,90)
  Comment              = Array of latitude values corresponding to the 
                         x,y grid coordinates [0,0], [0,66], [66,66], [66,0]


 Element

  Parameter Name        = LONGITUDE
  Definition            = Longitude of corner points of the grid 
  Format                = f6.3
  Type                  = float32
  Length                = 4 * float32 (16 bytes)
  Range                 = (-180,180)
  Comment               = Array of longitude values corresponding to the 
                          x,y grid coordinates [0,0], [0,66], [66,66], [66,0]


 Element

  Parameter Name        = Temporal_Res
  Definition            = Temporal resolution of the data set
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 = 
  Comment               = Possible values are "daily" or "monthly"


 Element

  Parameter Name        = Spatial_X_Res
  Definition            = Spatial resolution of data set in x direction
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 = 100.27 km
  Comment               =


 Element

  Parameter Name        = Spatial_Y_Res
  Definition            = Spatial resolution of data set in y direction
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 = 100.27 km
  Comment               =  


 Element

  Parameter Name        = PRODUCER_GRANULE_ID
  Definition            = Name of granule when generated on production system
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Unix system file name generated on POLES SCF system


 Element

  Parameter Name        = PRODUCER_DATE
  Definition            = Date granule was produced
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Example of value used for this attribute is 
                          "Mon May 16 11:21:38 1994"


 Element

  Parameter Name        = PRODUCER_PROGRAM
  Definition            = RCS header for production software
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Example of a value for this attribute is 
                          "$Header: /home/n1/PathP/development/src/l3
                           /gridgen/RCS/PPgridL2.c, v1.1 1994/05/11/23:08:09 
                           axel Exp axel $"


 Element
  
  Parameter Name        = PRODUCER_REVISION_DATE
  Definition            = Date of last modification to production program
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Example of value for this attribute is 
                          "Mon May 16 11:14:23 1994"


 Element

  Parameter Name        = PRODUCER_ARCHITECTURE
  Definition            = Production machine architecture and Operating System
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Example of the information provided by this 
                          attribute is "SunOS.4.1.3_UI node: nansen"


 Element

  Parameter Name        = PRODUCER_COMMENT
  Definition            = Any comment the producer feels necessary to add 
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Example of the information provided by this
                          attribute is "SunOS.4.1.3_UI node: nansen"


 Element

  Parameter Name        = PRODUCER_DOCUMENT
  Definition            = Document that describes this data set
  Format                = string
  Type                  = character
  Length                = Max 256
  Range                 =
  Comment               = Value for this attribute is "PATH-P_USERS_GUIDE.TXT"

Attributes that comprise the Scientific Data Sets object are defined by the following elements:



 Element

  Parameter Name        = LATITUDE_GRID
  Definition            = Latitude coordinate of each grid point
  Format                = f6.3
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees
  Size                  = 67 x 67
  Comment               = This Scientific Data (SD) is stored in an external SD
                          file: LatGrd.exhdf 


 Element

  Parameter Name        = LONGITUDE_GRID
  Definition            = Longitude coordinate of each grid point
  Format                = f6.3
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees
  Size                  = 67 x 67
  Comment               = This Scientific Data (SD) is stored in an external SD
                          file: LonGrd.exhdf


 Element

  Parameter Name        = TEMP
  Definition            = Temperatures [K] at pressure levels 
                          50, 70, 100, 300, 400, 500, 600, 700, 850 millibars
  Format                = f6.3
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin 
  Size                  = 9 x 67 x 67
  Comment               = 

 Element

  Parameter Name        = TEMP-SD
  Definition            = Time Standard Deviation of TEMP 
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin
  Size                  = 9 x 67 x 67
  Comment               =


 Element

  Parameter Name        = WVAPOR 
  Definition            = Precipital water [mm] of layers bounded by 300-400,
                          400-500, 500-700, 500-850, 850-1000 millibars
  Format                = f6.3
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = mm 
  Size                  = 5 x 67 x 67
  Comment               =

 Element

  Parameter Name        = WVAPOR-SD
  Definition            = Time Standard Deviation of WVAPOR
  Format                = f6.3
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = mm
  Size                  = 5 x 67 x 67
  Comment               =


 Element

  Parameter Name        = SKTEMP
  Definition            = Surface skin temperature [K] 
                          400-500, 500-700, 500-850, 850-1000 millibars
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin 
  Size                  = 67 x 67
  Comment               =

 
 Element

  Parameter Name        = SKTEMP-SD
  Definition            = Time Standard Deviation of SKTEMP
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = FCLD
  Definition            = Total effective cloud fraction [%]
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = percent 
  Size                  = 67 x 67
  Comment               = Effective cloud fraction is the retrieved 
                          radiatively effective cloud fraction and is the 
                          product of the actual cloud fraction and the 
                          cloud emissivity. This parameter corresponds to 
                          the actual cloud fraction if clouds had unit 
                          emissivity.

 Element

  Parameter Name        = FCLD-SD
  Definition            = Time Standard Deviation of FCLD[%]
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = percent
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = CLPRESS
  Definition            = Cloudtop pressure [mb]
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = millibars 
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = CLPRESS-SD
  Definition            = Time Standard Deviation of CLPRESS
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = millibars
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = CLTEMP 
  Definition            = Cloudtop temperature [K] 
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin
  Size                  = 67 x 67
  Comment               =

 Element

  Parameter Name        = CLTEMP-SD
  Definition            = Time Standard Deviation of CLTEMP
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = ZANGLE
  Definition            = Effective satellite zenith angle defined as the
                          arccosine of the average value of the cosines of
                          the cosines of the individual satellite zenith angles.
  Format                = f5.2
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = ZANGLE-SD
  Definition            = Time Standard Deviation of ZANGLE
  Format                = f5.2
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = EMISS
  Definition            = Surface emissivity at 50 GHz (MSU Channel 1)
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = 
  Size                  = 67 x 67
  Comment               = This variable may be used to provide a surface
                          type classification.


 Element

  Parameter Name        = EMISS-SD
  Definition            = Time Standard Deviation of EMISS
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 =
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = PBLSTRAT
  Definition            = Boundary layer bulk stratification (difference
                          in potential temperature between the surface and
                          at 900 mb.
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = PBLSTRAT-SD
  Definition            = Time Standard Deviation for PBLSTRAT
  Format                = f5.1
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees of Kelvin
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = Cg
  Definition            = Geostrophic drag coefficient over sea ice 
                          (Overland and Davidson, 1992). 
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = 
  Size                  = 67 x 67
  Comment               = This value is parameterized after Overland and 
                          Davidson, 1992. This variable is calculated only 
                          over sea ice.


 Element

  Parameter Name        = Cg-SD
  Definition            = Time Standard Deviation for Cg
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 =
  Size                  = 67 x 67
  Comment               =


 Element

  Parameter Name        = ALPHA
  Definition            = Turning angle between the geostrophic wind and the
                          surface wind over sea ice (Overland and Davidson, 
                          1992).
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees
  Size                  = 67 x 67
  Comment               = This variable is based on the parameterization of 
                          Overland and Davidson (1992) and is calculated only 
                          over sea ice. Positive values represent counter 
                          clockwise turning angles.


 Element

  Parameter Name        = ALPHA-SD
  Definition            = Time Standard Deviation for ALPHA
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = degrees
  Size                  = 67 x 67
  Comment               = 


 Element

  Parameter Name        = IIIreject
  Definition            = Number of III rejections per grid cell
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = counts
  Size                  = 67 x 67
  Comment               = IIIreject is the number of retrievals rejected for
                          an individual grid cell by the algorithm. Under
                          certain conditions the processing algorithm is
                          not able to perform a retrieval. These conditions
                          are often associated with thick clouds. Only actual
                          rejections are counted. A value of zero (0) may mean 
                          that no rejections occured or that no observations
                          were available for the respective grid cell.


 Element

  Parameter Name        = OBS 
  Definition            = Number of non-rejected observations per grid cell 
  Format                = f3.0
  Type                  = 32 bit floating point Scientific Data Set
  Units                 = counts
  Size                  = 67 x 67
  Comment               = The number of valid ovservations per cell. By 
                          examining the values of OBS and IIIreject, the
                          user can determine the fraction of rejected 
                          observations. The derived fraction may provide
                          an indication of how well the retrieved values 
                          represent atmospheric conditions for a given time
                          period.