Radial Graphic Product Decoder

The decoder GET_RADIAL_DATA returns information on the radar site, volume scan time, radar operating mode, and on the radar data itself. The array IFIELD() contains values 0-15, which can be converted to physical units by using the elements in output vector ICATS() through the relationship:

PHYSICAL VALUE = ICATS(IFIELD(I,J))

In general an IFIELD(,) of 0 indicates a value below the lowest data threshold. For velocity and spectrum width products, an IFIELD value of 0 indicates insufficient backscatterers within the volume to obtain a reliable estimate of the data there, not a radial velocity of zero. For velocity and spectrum width products, an IFIELD value of 15 indicates range-folded data.

Note that all input and output variables are INTEGER*4 except:

     IVAL(), IHDEADER(), ITRAILER() : BYTE or CHARACTER*1
     ICATT() : INTEGER*2
     IFIELD(,) : BYTE

EXPLANATION OF SUBROUTINE ARGUMENTS:

     CALL GET_RADIAL_DATA(IVAL,MSGLEN,ISITE,
     1  ISITE_LAT,ISITE_LON,ISITE_ELEV, 
     2  IYR,IMONTH,IDAY,IHR,IMINIT,ISEC,
     3  IPROD,MAXVAL,IVCP,IFIELD,MAXBINS,MAXRADIALS,
     4  IAZMUTH,IELEV,NBINS,NRADIALS,ICATT,ICATS,
     5  MAXVAL2,IYR1,IMONTH1,IDAY1,IHR1,IMINIT1,
     6  IYR2,IMONTH2,IDAY2,IHR2,IMINIT2,ISTM_SPD,ISTM_DIR,
     7  IHEADER,LEN_HEADER,ITRAILER,LEN_TRAILER,ICODE)

IVAL( )        =     BYTE OR CHARACTER*1 ARRAY CONTAINING THE
                     RADIAL PRODUCT, DIMENSIONED BY MSGLEN (INPUT)
MSGLEN         =     LENGTH OF INPUT PRODUCT, BYTES (OUTPUT)
ISITE          =     WSR-88D SITE IDENTIFICATION NUMBER (OUTPUT)
ISITE_LAT      =     SITE LATITUDE (øN), DEG X 1000 (OUTPUT)
ISITE_LON      =     SITE LONGIITUDE (øE), DEG X 1000 (OUTPUT)
ISITE_ELEV     =     SITE ELEVATION, M MSL (OUTPUT)
IYR,IMONTH,IDAY=     PRODUCT VOLUME SCAN DATE (OUTPUT)
IHR,IMINIT,ISEC=     PRODUCT VOLUME SCAN TIME, UTC (OUTPUT)
IPROD          =     PRODUCT CODE NUMBER (OUTPUT) (EG 19 FOR Z)
MAXVAL         =     MAXIMUM VALUE IN THE FIELD (INTEGER*2,OUTPUT),
                     FOR VELOCITY PRODUCTS, THE GREATEST INBOUND
                     (NEGATIVE) VELOCITY.
MAXVAL2        =     FOR VELOCITY PRODUCTS, THE GREATEST OUTBOUND
                     (POSITIVE) VELOCITY (INTEGER*2, OUTPUT)
ISTM_SPD,
ISTM_DIR       =     FOR STORM-RELATIVE VELOCITY PRODUCTS, THE
                     VELOCITY SUBTRACTED FROM BASE VELOCITY (DEG
                     AND KT) (OUTPUT)
IYR1,IMONTH1,
IDAY1          =     FOR VARIABLE-PERIOD PRECIPITATION
                     ACCUMULATION PRODUCTS, STARTING DATE OF
                     ACCUMULATION PD (OUTPUT)
                     IHR1,IMINIT1   =    FOR VARIABLE-PERIOD PRECIPITATION
                     ACCUMULATION PRODUCTS, STARTING TIME OF
                     ACCUMULATION PERIOD (OUTPUT)
IYR2,IMONTH2,
IDAY2          =     FOR VARIABLE-PERIOD PRECIPITATION
                     ACCUMULATION PRODUCTS, ENDING DATE OF
                     ACCUMULATION PD (OUTPUT)
IHR2,IMINIT2   =     FOR VARIABLE-PERIOD PRECIPITATION
                     ACCUMULATION PRODUCTS, ENDING TIME OF
                     ACCUMULATION PD (OUTPUT)
IVCP           =     OPERATING VOLUME COVERAGE PATTERN (OUTPUT)
IFIELD(,)      =     RETURNED VALUES (DATA LEVELS) FOR THE FIELD
                     (OUTPUT); A BYTE VARIABLE, 0-15.  DIMENSIONED
                     MAXBINS,MAXRADIALS IN CALLING ROUTINE.
IAZMUTH()      =     ANTENNA AZIMUTH DIRECTIONS (DEG X 10) FOR EACH
                     RADIAL (OUTPUT).  DIMENSIONED BY MAXRADIALS IN
                     CALLING ROUTINE
IELEV          =     ANTENNA ELEVATION ANGLE, DEG X 10 (OUTPUT)
NBINS,NRADIALS =     NUMBER OF RANGE BINS AND RADIALS IN THE
                     MESSAGE (OUTPUT)
ICATT()        =     CATEGORY-INTERVAL VALUES TAKEN DIRECTLY FROM
                     PRODUCT HEADER (OUTPUT, INTEGER*2).  SHOULD BE
                     DIMENSIONED BY 16 OR 0:15 IN CALLING ROUTINE.
ICATS()        =     CATEGORY-INTERVAL VALUES IN PHYSICAL UNITS
                     (OUTPUT).  DIMENSIONED BY 16 OR 0:15 IN CALLING
                     ROUTINE
IHEADER()      =     BYTE ARRAY WITH COPY OF HEADER.  SHOULD BE
                     DIMENSIONED 160 IN CALLING ROUTINE (OUTPUT)
LEN_HEADER     =     ACTUAL NUMBER OF BYTES OF INFORMATION IN
                     IHEADER() (OUTPUT)
ITRAILER()     =     CHARACTER*1 ARRAY WITH TEXT INFORMATION
                     ATTACHED AT END OF FILE (IF ANY). SHOULD BE
                     DIMENSIONED BY20 000 IN CALLING ROUTINE (OUTPUT)
LEN_TRAILER    =     ACTUAL NUMBER OF BYTES OF DATA IN ITRAILER(). 
                     WILL BE SET 0 IF NO TRAILER EXISTS(OUTPUT)
ICODE          =     RETURN CODE, CONDITIONS AS FOLLOWS:
                     0 : DATA RETURNED OK
                     2 : NOT A RADIAL GRAPHIC PRODUCT
                     3 : MAXRADIALS OR MAXBINS IS TOO SMALL
                     4 : PRODUCT LENGTH GREATER THAN MSGLEN

Known Deficiencies:

None

Related Documents:

Federal Meteorological Handbook 11: Doppler Radar Meteorological Observations Part C, WSR-88D Products and Algorithms.

Interface Control Document for Product Specification (Document Number 2620003A, WSR-88D OSF, June 26, 1998)

Interface Control Document for the RPG Associated PUP ( Document Number 2620001A, WSR-88D OSF, June 26, 1998) WSR-88D Digital Hybrid Scan Decoder

Change History Log:

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