CCSD1Z00000100000052CCSD1R00000300000032
DELIMITER=EOF;
TYPE=CCSD1F000001;
CCSD1C00000400000052
ADI=NURSML03;
SUD=NURSML01;
SUD=NURSML02;
SUD=NURSML04;
CCSD1R00000300000032
DELIMITER=EOF;
TYPE=CCSD1D000002;





                    UPPER ATMOSPHERE RESEARCH SATELLITE
                                     
                                     
                          MICROWAVE LIMB SOUNDER
                                     
                                     
                                     
                       Standard Formatted Data Units
                                     
                          File Class Document for
                                     
                          MLS Level 3AT Data File
                                     
                                     
                                     
                                     
                                     
                                     
                                     
                                     
                                     
                                     
                                     
                                     
                              June 1996
                                     
                                     
                                     
                                     
                         J.R. Burke and T. A. Lungu  
                                     
                         Jet Propulsion Laboratory
                    California Institute of Technology,
                           Pasadena, California
                                     
                                     
                                     
                                     
                                     
                                     
          
          
          
          
          UPPER ATMOSPHERE RESEARCH SATELLITE
          
          MICROWAVE LIMB SOUNDER
          
          
          
          
          Standard Formatted Data Units Document List:
          
          
          NURS1I00ML02        Whole Data Set
          
          NURS1I00ML01        File Class:  Level 2 Data
          
          NURS1I00ML03   **   File Class:  Level 3AT Data
          
          NURS1I00ML04        File Class:  Level 3TP Parameter
          
          NURS1I00ML05        File Class:  Level 3AL Data
          
          NURS1I00ML06        File Class:  Level 3LP Parameter
          
          
                        (**   this document)
          
          
          
          
          
          
          


          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
          
UARS MLS SFDU FILE CLASS DOCUMENT FOR:
======================================

MLS LEVEL 3AT DATA FILE
-----------------------

Introduction

The organization  of Standard  Formatted Data Units (SFDU) documentation is
hierarchical, with  the top  level describing  the entire data set, and the
bottom level  describing a data item within a record.  The hierarchy levels
are:   Whole Data  Set, File Class, Record, and Field.  A separate document
is required  for the Whole Data Set and for each File Class.  For MLS there
exist five  SFDU File  Classes:   the Level  2 Data Set, the Level 3AT Data
Set, the Level 3AL Data Set, the Level 3TP Parameter File and the Level 3LP
Parameter File.   This  is the  Document describing  the MLS File Class for
Level 3AT  Data.   The implementation for MLS data follows the standard for
UARS data  which is  described in  Computer Sciences  Corporation,  CSC/SD-
86/6704/UD6, UARS  Central Data  Handling Facility  (CDHF) Software  System
(UCSS) Programmer's Guide to Production Software Support Services, 1993.

A Level  3AT Data  File consists  of  a  time-ordered  collection  of  data
records.   Each record  contains a  single array  of  data  values  of  one
atmospheric parameter  (either mixing  ratio for  a  measured  species,  or
temperature) for a specific time.  The reference time values at which Level
3AT measurements  apply are  common across  Level 3AT  files from  all UARS
instruments.   The Level  3AT data  record time is (by UARS definition) the
time associated  with "SMIF  0 of SMAF 32 of the EMAF at Level 0", and this
corresponds to  the mid-point  of the  MLS 65.536 second major frame during
which the  instrument  completes  a  vertical  scan  to  make  the  profile
measurements.

Each record  also contains  an array of "Quality" values with one value for
each data  value.   These quality values are estimated uncertainties of the
data obtained  from the square root of the diagonal terms of the covariance
matrix (and are multiplied by -1 when the ratio of estimated uncertainty to
a priori  uncertainty is  greater than  0.5.)  Additional indicators of the
quality of  the data are contained in the corresponding Level 3TP Parameter
file.

The MLS Production Processing Software provides data values for Type (which
has the  constant value  MLS), Species/Subtype, geodetic latitude, geodetic
longitude, data, quality, UARS Day, and profile time.

---------------------------------------------------------------------------

File Class

FILE_CLASS_NAME:      Level3AT_Data

RECORD_TYPE_NAMES:    There are four record types: SFDU_Label, File_Label_
                      Record, Continuation_Label_Record, Data_Record

ALGORITHMS:           Information on the algorithms used for retrieval of
                      geophysical data from the instrument measurements is
                      provided in the UARS MLS SFDU File Class Document for
                      the MLS Level 2 Data File.
                      
                      Each data record contains a single retrieved profile
                      for one of the parameters measured by the MLS (either
                      a species mixing ratio or temperature), together with
                      estimated uncertainties as the primary indicator of
                      data quality.  The profiles are at the times, and in
                      the sequence, as measured by the instrument but are
                      on the standard UARS pressure grid rather than the
                      coarser grid used by MLS Production Processing
                      software for retrieval.  The Level 3AT profile values
                      on even-indexed pressure levels are obtained from
                      corresponding elements in the Level 2 PROFILE vector,
                      and on odd-indexed levels by averaging adjacent even-
                      indexed values.  The Quality values are obtained in
                      a similar manner from data in the Level 2 file, and
                      additional quality information is contained in the
                      Level 3TP Parameter file.

                      The MLS Level 3AT file is produced by calls to the
                      UARS CDHF standard open file and write routines
                      provided by the UARS CDHF Software System (UCSS)
                      Production Software Support Services.  These routines
                      generate the SFDU_Label record, as well as values for
                      certain fields within the other records, including
                      Local_Solar_Time and Solar_ Zenith_Angle.

FILE_CLASS_SYNTAX:    Number of records is specified in File_Label_Record.
                      List of Record Types in file:
                      #1: SFDU_Label
                      #2: File_Label_Record
                      #3: Continuation_Label_Record
                          Zero or more as specified in File_Label_Record
                      #4: Data_Record
                          One or more as specified in the File_Label_Record

FILE_CLASS_FIELD_RELATIONSHIPS:    Files of the Level 3AT class contain
                      information about retrieved profiles which is derived
                      directly from similar information in the Level 2
                      file.  Files of the Level 3AL class contain similar
                      information.  Fields which are used in both the Level
                      3AT and Level 3AL File Classes are similar, if not
                      identical.  For clarity, all fields are defined in
                      this MLS SFDU File Class document for Level 3AT.

FILE_CLASS_MISC:      The Version 4.22 MLS Software creates Level 3AT
                      Class Files for seven geophysical parameters:  Chlorine
                      monoxide, ozone(205), ozone(183), water vapor,
                      temperature, nitric acid, and sulfur dioxide.
                      The Version 4.11/4.12 MLS Software does not create Level
                      3AT for nitric acid.

---------------------------------------------------------------------------





Record Type 1

1. SFDU_Label
-------------
RECORD_NAME:            SFDU_Label
RECORD_STRUCTURE:       Fixed Length
RECORD_LENGTH:          40 Bytes
RECORD_FIELD_NAMES:     Tz_Field, Lz_Field, Ti_Field, Li_Field
RECORD_SYNTAX:          4 Fields
                        #1: Tz_Field
                        #2: Lz_Field
                        #3: Ti_Field
                        #4: Li_Field


Fields

1.1 Tz_Field
------------
FIELD_NAME:             Tz_Field
FIELD_SYNTAX:           ASCII Character*12 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      SFDU Type (Tz) Field.
                        Constant Value = 'CCSD1Z000001'.
FIELD_REPRESENTATION:   12A
FIELD_DISPLAY_FORMAT:   A12

1.2 Lz_Field
------------
FIELD_NAME:             Lz_Field
FIELD_SYNTAX:           ASCII Character*8 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      SFDU Length (Lz) Field.  20 + l
                        where l is the length of the UARS file.
                        Right justified, zero filled
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

1.3 Ti_Field
------------
FIELD_NAME:             Ti_Field
FIELD_SYNTAX:           ASCII Character*12 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      SFDU Type (Ti) Field.
                        Constant value = 'NURS1I00ML03'
FIELD_REPRESENTATION:   12A
FIELD_DISPLAY_FORMAT:   A12

1.4 Li_Field
------------
FIELD_NAME:             Li_Field
FIELD_SYNTAX:           ASCII Character*8 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      SFDU Length (Lz) Field.  Length of UARS file.
                        Right justified, zero filled
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

---------------------------------------------------------------------------


Record Type 2

2. File_Label_Record
--------------------
RECORD_NAME:            File_Label_Record
RECORD_STRUCTURE:       Variable Length
RECORD_LENGTH:          Max (148 + 28 * n, length of Data_Record)
                        where n =
                         Value (Number_of_Time/Version_Entries_in_Record)

RECORD_FIELD_NAMES:     in alphabetical order:
                        Base_Index_Of_Data_Point_Values
                        CCB_Version_Number
                        Data_Level
                        Data_Subtype_Or_Species
                        Day_Of_Year_For_First_Data_Record
                        Day_Of_Year_For_Last_Data_Record
                        File_Creation_Time_In_VAX_VMS_ASCII_Format
                        File_Cycle_Number
                        Format_Version_Number
                        Instrument_Identifier
                        Milliseconds_Of_Day_For_First_Data_Record
                        Milliseconds_Of_Day_For_Last_Data_Record
                        Number_Of_Continuation_Records_For_File_Label
                        Number_Of_Data_Points_Per_Record
                        Number_Of_Physical_Records_In_File
                        Number_Of_Time/Version_Entries_In_Record
                        Physical_Record_Count
                        Record_Length_In_Bytes
                        Record_Type
                        Satellite_Identifier
                        Total_Number_Of_Time/Version_Entries_In_File
                        UARS_Day_Number
                        Year_For_First_Data_Record
                        Year_For_Last_Data_Record
                        Version_Entries
                        Virtual_File_Flag

RECORD_SYNTAX:          26 Fields in the following order:
                        #1 : Satellite_Identifier
                        #2 : Record_Type
                        #3 : Instrument_Identifier
                        #4 : Data_Subtype_Or_Species
                        #5 : Format_Version_Number
                        #6 : Physical_Record_Count
                        #7 : Number_Of_Continuation_Records_For_File_Label
                        #8 : Number_Of_Physical_Records_In_File
                        #9 : File_Creation_Time_In_VAX_VMS_ASCII_Format
                        #10: Year_For_First_Data_Record
                        #11: Day_Of_Year_For_First_Data_Record
                        #12: Milliseconds_Of_Day_For_First_Data_Record
                        #13: Year_For_Last_Data_Record
                        #14: Day_Of_Year_For_Last_Data_Record
                        #15: Milliseconds_Of_Day_For_Last_Data_Record
                        #16: Data_Level
                        #17: UARS_Day_Number
                        #18: Number_Of_Data_Points_Per_Record
                        #19: Base_Index_Of_Data_Point_Values
                        #20: Record_Length_In_Bytes
                        #21: CCB_Version_Number
                        #22: File_Cycle_Number
                        #23: Virtual_File_Flag
                        #24: Total_Number_Of_Time/Version_Entries_In_File
                        #25: Number_Of_Time/Version_Entries_In_Record
                        #26: Version_Entries


Fields

2.1 Satellite_Identifier
------------------------
FIELD_NAME:             Satellite_Identifier
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Satellite identifier.  Constant value 'UARS'
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.2 Record_Type
---------------
FIELD_NAME:             Record_Type
FIELD_SYNTAX:           ASCII Character*2 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Record type.  Constant value ' 1' indicates a
                        file label record.
FIELD_REPRESENTATION:   2A
FIELD_DISPLAY_FORMAT:   A2

2.3 Instrument_Identifier
-------------------------
FIELD_NAME:             Instrument_Identifier
FIELD_MNEMONIC:         Data_Type
FIELD_SYNTAX:           ASCII Character*12 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Instrument identifier.
                        Constant value = 'MLS         '
FIELD_REPRESENTATION:   12A
FIELD_DISPLAY_FORMAT:   A12

2.4 Data_Subtype_Or_Species
---------------------------
FIELD_NAME:             Data_Subtype_Or_Species
FIELD_MNEMONIC:         Subtype
FIELD_SYNTAX:           ASCII Character*12 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Data subtype or species.
                        Left justified, blank filled.
                        The seven subtypes/species for MLS are: CLO, O3_205,
                        O3_183, H2O, TEMP, SO2 and HNO3
FIELD_REPRESENTATION:   12A
FIELD_DISPLAY_FORMAT:   A12

2.5 Format_Version_Number
-------------------------
FIELD_NAME:             Format_Version_Number
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Format version number.  Constant value '   1'
                        indicates that this is the first version of the
                        Level 3AT file structure.
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.6 Physical_Record_Count
-------------------------
FIELD_NAME:             Physical_Record_Count
FIELD_SYNTAX:           ASCII character*8 string
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Physical record count.  Constant value '       1'
                        indicates the label record is the logical first
                        record in the file.
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

2.7 Number_Of_Continuation_Records_For_File_Label
-------------------------------------------------
FIELD_NAME:             Number_Of_Continuation_Records_For_File_Label
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 0
FIELD_DESCRIPTION:      Number of continuation records for file label
                        for a virtual file (a level 3AT file containing
                        a user specified time range that is not on day
                        boundaries).
                        Right justified, blank filled
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.8 Number_Of_Physical_Records_In_File
--------------------------------------
FIELD_NAME:             Number_Of_Physical_Records_In_File
FIELD_SYNTAX:           ASCII Character*8 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Number of physical records in file.
                        Right justified, blank filled.
                        Does not count SFDU label record.
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

2.9 File_Creation_Time_In_VAX_VMS_ASCII_Format
----------------------------------------------
FIELD_NAME:             File_Creation_Time_In_VAX_VMS_ASCII_Format
FIELD_SYNTAX:           ASCII Character*23 String
FIELD_UNITS:            dd-mmm-yyyy hh:mm:ss.cc
FIELD_RESOLUTION:       0.01 second
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      File creation time in VAX VMS ASCII format
                        indicates the date and time the file was cataloged
                        in the UCSS.
FIELD_REPRESENTATION:   23A
FIELD_DISPLAY_FORMAT:   A23

2.10 Year_For_First_Data_Record
-------------------------------
FIELD_NAME:             Year_For_First_Data_Record
FIELD_SYNTAX:           ASCII Character*3 String
FIELD_UNITS:            Years since 1900
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Year for first data record.  Value is Year-1900.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   3A
FIELD_DISPLAY_FORMAT:   A3

2.11 Day_Of_Year_For_First_Data_Record
--------------------------------------
FIELD_NAME:             Day_Of_Year_For_First_Data_Record
FIELD_SYNTAX:           ASCII Character*3 String
FIELD_UNITS:            Day of Year
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 1, <= 366
FIELD_DESCRIPTION:      Day of year for first data record.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   3A
FIELD_DISPLAY_FORMAT:   A3

2.12 Milliseconds_Of_Day_For_First_Data_Record
----------------------------------------------
FIELD_NAME:             Milliseconds_Of_Day_For_First_Data_Record
FIELD_SYNTAX:           ASCII Character*8 String
FIELD_UNITS:            Milliseconds
FIELD_RESOLUTION:       1 millisecond
FIELD_RANGE:            Integer >=0, <= 86399999
FIELD_DESCRIPTION:      Milliseconds of day for first data record.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

2.13 Year_For_Last_Data_Record
------------------------------
FIELD_NAME:             Year_For_Last_Data_Record
FIELD_SYNTAX:           ASCII Character*3 String
FIELD_UNITS:            Years since 1900
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Year for last data record.  Value is Year-1900.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   3A
FIELD_DISPLAY_FORMAT:   A3

2.14 Day_Of_Year_For_Last_Data_Record
-------------------------------------
FIELD_NAME:             Day_Of_Year_For_Last_Data_Record
FIELD_SYNTAX:           ASCII Character*3 String
FIELD_UNITS:            Day of year
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 1, <= 366
FIELD_DESCRIPTION:      Day of year for last data record.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   3A
FIELD_DISPLAY_FORMAT:   A3

2.15 Milliseconds_Of_Day_For_Last_Data_Record
---------------------------------------------
FIELD_NAME:             Milliseconds_Of_Day_For_Last_Data_Record
FIELD_SYNTAX:           ASCII Character*8 String
FIELD_UNITS:            Milliseconds
FIELD_RESOLUTION:       1 millisecond
FIELD_RANGE:            Integer >= 0, <= 86399999
FIELD_DESCRIPTION:      Milliseconds of day for last data record.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

2.16 Data_Level
---------------
FIELD_NAME:             Data_Level
FIELD_SYNTAX:           ASCII Character*3 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Data level.  Constant value '3AT' indicates
                        data that has been placed on the standard
                        UARS time and pressure grid.
FIELD_REPRESENTATION:   3A
FIELD_DISPLAY_FORMAT:   A3

2.17 UARS_Day_Number
--------------------
FIELD_NAME:             UARS_Day_Number
FIELD_MNEMONIC:         UARS_Day
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            Days
FIELD_RESOLUTION:       1 day
FIELD_RANGE:            Integer >= 1
FIELD_DESCRIPTION:      UARS day number (UARS day 1 = September 12, 1991)
                        Right justified, blank filled.
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.18 Number_Of_Data_Points_Per_Record
-------------------------------------
FIELD_NAME:             Number_Of_Data_Points_Per_Record
FIELD_MNEMONIC:         Max_Points
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 1, <= 1000
FIELD_DESCRIPTION:      Number of data points per record.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.19 Base_Index_Of_Data_Point_Values
------------------------------------
FIELD_NAME:             Base_Index_Of_Data_Point_Values
FIELD_MNEMONIC:         Base_Index
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 0, <= 100
FIELD_DESCRIPTION:      Base_Index is the starting (lowest) grid index for
                        the standard UARS grid present in the data array of
                        the file (i.e. the data entry in the first element
                        in the DATA3A array is the data value for the UARS
                        standard grid at the position indicated by the
                        value of Base_ Index).  The base_index, together
                        with the Max_Points, determine the dimensions of
                        the Level 3 array.  The UARS Standard grids are
                        defined in Appendix E of the UCSS Programmer's
                        Guide.  Right justified, blank filled.
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.20 Record_Length_In_Bytes
---------------------------
FIELD_NAME:             Record_Length_In_Bytes
FIELD_SYNTAX:           ASCII Character*5 String
FIELD_UNITS:            Bytes
FIELD_RESOLUTION:       4 bytes
FIELD_RANGE:            Integer >= 148, <= 2216
FIELD_DESCRIPTION:      Record length in bytes.
                        Right justified, blank filled.
                        Value is 4*Integerpart ((Max(148, 64 + 8*n) + 3)/4)
                        where n = Value (Number_Of_Data_Points_per_Record)
FIELD_REPRESENTATION:   5A
FIELD_DISPLAY_FORMAT:   A5

2.21 CCB_Version_Number
-----------------------
FIELD_NAME:             CCB_Version_Number
FIELD_SYNTAX:           ASCII Character*9 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >=1, <= 9999
FIELD_DESCRIPTION:      Version number assigned by the UCSS Configuration
                        Control Board in conjunction with the Principal
                        Investigator to differentiate versions of data.
                        The value is 4, for data products from MLS Product-
                        ion Processing Software Version 4.22 and 3 for 
                        MLS Production Processing Software Version 4.11/v12
                        Right justified, blank filled
FIELD_REPRESENTATION:   9A
FIELD_DISPLAY_FORMAT:   A9

2.22 File_Cycle_Number
----------------------
FIELD_NAME:             File_Cycle_Number
FIELD_SYNTAX:           ASCII Character*5 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >=1, <= 31
FIELD_DESCRIPTION:      File cycle number right justified, blank filled
                        Supplied only during file creation by a Remote
                        Access Computer data transfer, otherwise undefined
                        The cycle number is incremented if necessary to
                        provide a unique catalog entry at the UARS CDHF.
FIELD_REPRESENTATION:   5A
FIELD_DISPLAY_FORMAT:   A5

2.23 Virtual_File_Flag
----------------------
FIELD_NAME:             Virtual_File_Flag
FIELD_SYNTAX:           ASCII Character*1 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      The Virtual_File_Flag is set to ' '  if a file is
                        a production file containing all the available data
                        for one specific day or 'V' if the file is created
                        by a Remote Access Computer data transfer where a
                        user specified time range is not on day boundaries.
FIELD_REPRESENTATION:   1A
FIELD_DISPLAY_FORMAT:   A1

2.24 Total_Number_Of_Time/Version_Entries_In_File
-------------------------------------------------
FIELD_NAME:             Total_Number_Of_Time/Version_Entries_In_File
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 0
FIELD_DESCRIPTION:      Total number of time/version entries in file.
                        Only used for for virtual files created via RAC
                        data transfer.  Right justified, blank filled.
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.25 Number_Of_Time/Version_Entries_In_Record
---------------------------------------------
FIELD_NAME:             Number_Of_Time/Version_Entries_In_Record
FIELD_SYNTAX:           ASCII Character*4 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 0
FIELD_DESCRIPTION:      Number of time/version entries in record.
                        Right justified, blank filled.
FIELD_REPRESENTATION:   4A
FIELD_DISPLAY_FORMAT:   A4

2.26 Version_Entries
--------------------
FIELD_NAME:             Version_Entries
FIELD_SYNTAX:           ASCII Character*28 String 1-D Array (n), where n is
                        value (Number_Of_Time/Version_Entries_In_Record)
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      List of version entries.
                        Each version entry contains:
                        Version_Entries (1:3)   start year
                        Version_Entries (4:6)   start day of year
                        Version_Entries (7:14)  start milliseconds of day
                        Version_Entries (15:24) version number
                        Version_Entries (24:28) cycle number
FIELD_REPRESENTATION:   n(28A)
FIELD_DISPLAY_FORMAT:   nA28

---------------------------------------------------------------------------

Record Type 3

3. Continuation_Label_Record
----------------------------
RECORD_NAME:            Continuation_Label_Record
RECORD_STRUCTURE:       Variable Length
RECORD_LENGTH:          Max (48 + 28 * n, length of Data_Record)
                        where n =
                         Value (Number_of_Time/Version_Entries_in_Record)

RECORD_FIELD_NAMES:     in alphabetical order:
                        Data_Subtype_Or_Species
                        Format_Version_Number
                        Instrument_Identifier
                        Number_Of_Time/Version_Entries_In_Record
                        Physical_Record_Count
                        Record_Type
                        Satellite_Identifier
                        Spare
                        Version_Entries

RECORD_SYNTAX:          9  Fields in the following order:
                        #1 : Satellite_Identifier
                        #2 : Record_Type
                        #3 : Instrument_Identifier
                        #4 : Data_Subtype_Or_Species
                        #5 : Format_Version_Number
                        #6 : Physical_Record_Count
                        #7 : Number_Of_Time/Version_Entries_In_Record
                        #8 : Spare
                        #9 : Version_Entries


Fields

All definitions are as given above in File_Label_Record, except:

3.2 Record_Type
---------------
FIELD_NAME:             Record_Type
FIELD_SYNTAX:           ASCII Character*2 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Record type.  Constant value ' 2' indicates a
                        continuation label record.
FIELD_REPRESENTATION:   2A
FIELD_DISPLAY_FORMAT:   A2

3.6 Physical_Record_Count
-------------------------
FIELD_NAME:             Physical_Record_Count
FIELD_SYNTAX:           ASCII character*8 string
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Physical record count.  Constant value '       2'
                        indicates the continuation label record is the
                        logical second record in the file.
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

3.8 Spare
---------
FIELD_NAME:             Spare
FIELD_SYNTAX:           ASCII Character*2 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Spare.  Field contents undefined.
FIELD_REPRESENTATION:   2A
FIELD_DISPLAY_FORMAT:   A2

---------------------------------------------------------------------------


Record Type 4

4. Data_Record
--------------
RECORD_NAME:            Data_Record
RECORD_STRUCTURE:       Variable Length
RECORD_LENGTH:          Max (64 + 4 * n, length of File_Label_Record)
                        where
                        n = Value (Total_Number_of_Points_in_the_Record)
RECORD_FIELD_NAMES:     in alphabetical order:
                        Data
                        Instrument_Identifier
                        Latitude
                        Local_Solar_Time
                        Longitude
                        Number_Of_Actual_Points
                        Physical_Record_Count
                        Quality
                        Record_Time_In_UDTF_Format
                        Record_Type
                        Satellite_Identifier
                        Solar_Zenith_Angle
                        Spare
                        Starting_Index_Of_First_Actual_Point
                        Total_Number_Of_Points_In_The_Record

RECORD_SYNTAX:          15 Fields in the following order:
                        #1 : Satellite_Identifier
                        #2 : Record_Type
                        #3 : Instrument_Identifier
                        #4 : Physical_Record_Count
                        #5 : Spare
                        #6 : Total_Number_Of_Points_In_The_Record
                        #7 : Number_Of_Actual_Points
                        #8 : Starting_Index_Of_First_Actual_Point
                        #9 : Record_Time_In_UDTF_Format
                        #10: Latitude
                        #11: Longitude
                        #12: Local_Solar_Time
                        #13: Solar_Zenith_Angle
                        #14: Data
                        #15: Quality


Fields

4.1 Satellite_Identifier
------------------------
Defined in 2.1 above.

4.2 Record_Type
---------------
FIELD_NAME:             Record_Type
FIELD_SYNTAX:           ASCII Character*2 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Record type.
                        Constant value ' 3' for a data record.
FIELD_REPRESENTATION:   2A
FIELD_DISPLAY_FORMAT:   A2

4.3 Instrument_Identifier
-------------------------
Defined in 2.3 above.

FIELD_NAME:             Instrument_Identifier
FIELD_MNEMONIC:         Data_Type
FIELD_SYNTAX:           ASCII Character*12 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Constant value 'MLS'.
FIELD_REPRESENTATION:   12A
FIELD_DISPLAY_FORMAT:   A12

4.4 Physical_Record_Count
-------------------------
FIELD_NAME:             Physical_Record_Count
FIELD_SYNTAX:           ASCII Character*8 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 2
FIELD_DESCRIPTION:      Physical record count.
                        Right justified, blank filled.
                        Does not count SFDU label record.
FIELD_REPRESENTATION:   8A
FIELD_DISPLAY_FORMAT:   A8

4.5 Spare
---------
FIELD_NAME:             Spare
FIELD_SYNTAX:           ASCII Character*2 String
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      Spare.  Constant value '00'
FIELD_REPRESENTATION:   2A
FIELD_DISPLAY_FORMAT:   A2

4.6 Total_Number_Of_Points_In_The_Record
----------------------------------------
FIELD_NAME:             Total_Number_Of_Points_In_The_Record
FIELD_MNEMONIC:         Max_Points
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 1, <= 1000
FIELD_DESCRIPTION:      Maximum number of data points in the data array.
                        This value is different for each MLS sub-type
                        (species/temperature) and is specified below in the
                        table for the Data field definition, 4.14.
FIELD_REPRESENTATION:   VI4
FIELD_DISPLAY_FORMAT:   I4

4.7 Number_Of_Actual_Points
---------------------------
FIELD_NAME:             Number_Of_Actual_Points
FIELD_MNEMONIC:         Num_Points
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 1, <= 1000
FIELD_DESCRIPTION:      Number of actual elements in the data array.
FIELD_REPRESENTATION:   VI4
FIELD_DISPLAY_FORMAT:   I4

4.8 Starting_Index_Of_First_Actual_Point
----------------------------------------
FIELD_NAME:             Starting_Index_Of_First_Actual_Point
FIELD_MNEMONIC:         Start_Index
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            n/a
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            Integer >= 0, <= 100
FIELD_DESCRIPTION:      Standard UARS Pressure Level Index (see Appendix E
                        in the Programmer's Guide referenced in the
                        Introduction above) for the first actual element in
                        DATA3A array.
FIELD_REPRESENTATION:   VI4
FIELD_DISPLAY_FORMAT:   I4

4.9 Record_Time_In_UDTF_Format
-------------------------------
FIELD_NAME:             Record_Time_In_UDTF_Format
FIELD_MNEMONIC:         Strt_Dattim
FIELD_SYNTAX:           1-D Array (2)
FIELD_UNITS:            1 millisecond
FIELD_RESOLUTION:       1 millisecond
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      UARS reference time in UDTF format for this record.
FIELD_REPRESENTATION:   2VI4
FIELD_DISPLAY_FORMAT:   I5,I8

4.10 Latitude
--------------
FIELD_NAME:             Latitude
FIELD_MNEMONIC:         REF_LAT
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            Degrees
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            >= -88.5, <= 88.5
FIELD_DESCRIPTION:      Geodetic latitude at the UARS reference time.
                        Value provided by the MLS production software
                        from Orbit/Attitude Services (OAS) data.
FIELD_REPRESENTATION:   VR4
FIELD_DISPLAY_FORMAT:   F7.3

4.11 Longitude
--------------
FIELD_NAME:             Longitude
FIELD_MNEMONIC:         REF_LONG
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            Degrees
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            >= 0, < 360.0
FIELD_DESCRIPTION:      Geodetic longitude, value provided by the MLS
                        production software from OAS data.
FIELD_REPRESENTATION:   VR4
FIELD_DISPLAY_FORMAT:   F7.3

4.12 Local_Solar_Time
---------------------
FIELD_NAME:             Local_Solar_Time
FIELD_MNEMONIC:         LST
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            Hours
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            0 to 24
FIELD_DESCRIPTION:      Local solar time at limb tangent point at record
                        time, generated by UCSS Production Software Support
                        Services.
FIELD_REPRESENTATION:   VR4
FIELD_DISPLAY_FORMAT:   F7.3

4.13 Solar_Zenith_Angle
-----------------------
FIELD_NAME:             Solar_Zenith_Angle
FIELD_MNEMONIC:         SZA
FIELD_SYNTAX:           Scalar
FIELD_UNITS:            Degrees
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            0 to 180
FIELD_DESCRIPTION:      Solar zenith angle at tangent point at record time
                        generated by UCSS Production Software Support
                        Services.
FIELD_REPRESENTATION:   VR4
FIELD_DISPLAY_FORMAT:   F7.3

4.14 Data
---------
FIELD_NAME:             Data
FIELD_MNEMONIC:         DATA3A
FIELD_SYNTAX:           1-D Array (n), where n is value (Total_Number_Of_
                        Points_In_The_Record)
FIELD_UNITS:            Volume mixing ratio (for species), Degrees K (for
                        Temperature)
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a

FIELD_DESCRIPTION:      DATA3A is a one dimensional array where the index,
                        offset by Start_Index, is associated with the
                        element number in the UARS standard pressure
                        referenced array.  The array values are a profile
                        of species volume mixing ratio or temperature.
                        Array elements corresponding to even indices in the
                        standard array are values retrieved by the MLS
                        software while the elements for odd indices are the
                        averages of values from adjacent even-indexed
                        levels.  The following Table shows the values of:
                        Total_Number_Of_Points_In_The_Record (= Number_of_
                        Data_Points_per_Record) (NDPR) and Base_Index_Of_
                        Data_Point_Values (BIDPV) for each of the sub-types
                        retrieved by MLS:
                        
                                Sub-type         NDPR          BIDPV
                                -------------------------------------
                                CLO               19             2
                                O3_205            37             2
                                O3_183            37             2
                                H2O               39             0
                                TEMP              43             0
                                SO2               15             2
                                HNO3              19             2

FIELD_REPRESENTATION:   NVR4
FIELD_DISPLAY_FORMAT:   E12.3
FIELD_FILL_CODE:        INVALID_REAL_NUMBER X'00008000'

4.15 Quality
------------
FIELD_NAME:             Quality
FIELD_MNEMONIC:         Qual
FIELD_SYNTAX:           1-D Array (n), where n is value (Total_Number_Of_
                        Points_In_The_Record)
FIELD_UNITS:            Volume mixing ratio (for species), Degrees K (for
                        Temperature)
FIELD_RESOLUTION:       n/a
FIELD_RANGE:            n/a
FIELD_DESCRIPTION:      One dimensional array containing quality
                        information associated with the data values in
                        DATA3A.  For the Level 2 retrieved profiles, these
                        values are the square roots of the diagonal terms
                        of the covariance matrix.  They are multiplied by
                        -1 when the ratio of estimated uncertainty to a
                        priori uncertainty is greater than 0.5.  For the
                        Level 3AT file, array elements corresponding to
                        even indices in the standard array are values from
                        the Level 2 File while the elements for odd indices
                        are the averages of values from adjacent even-
                        indexed levels.  Scientific analyses of the MLS
                        data must include due consideration of these
                        quality values, as well as additional quality
                        indicators in the Level 3TP Parameter file, so that
                        the validity of any conclusions is not compromised.
FIELD_REPRESENTATION:   NVR4
FIELD_DISPLAY_FORMAT:   E12.3
FIELD_FILL_CODE:        INVALID_REAL_NUMBER X'00008000'

---------------------------------------------------------------------------
End of document. UARS MLS SFDU File Class Level 3AT Data File. June, 1996