November 20, 1996

MEMORANDUM TO:  Record
FROM:           Dennis A. Keyser -- W/NP22
Subject:        Changes to OI/SSI-Data Preprocessor
                (July 12, 1995 Version -- UPDATE # 6)

The July 12, 1995 version of the data preprocessor program
(PREPDATA) was updated for the sixth time.  UPDATE #6 was
implemented on 1200 UTC 20 November 1996 on the CRAY.  All
changes now affect only OBUFR = TRUE switch.  Except where noted,
the changes below affect both the GLOBAL and RGL/ETA models.

*********************  U P D A T E   # 6  ***********************


I.  GENERAL CHANGES

      1) Namelist switch IRTRV now dimensioned (5,6) instead of
(5,6,2) since interactive retrievals are no longer possible.

      2) The true NMCEDS file is now always in IUNIT(6) and the
JBUFR file is always in IUNIT(7), regradless of whether the
unpacked NMCEDS format is returned or the 40-level retrieval/28
radiance format is returned.
 
      3) The 16-bit PREPDA data set in IUNIT(11) is no longer
written to. This is now HARDWIRED, although commented-out logic
still allows for it.

      4) New BUFRLIB subroutine DATEBF is now called to get
center date for satellite retrieval JBUFR data set in subroutines
SATEDS and SATBFR.  This simplifies the other time checking
procedures.

      5) Added new namelist switches TOVRAD (default is FALSE)
and TOVRTV (default is FALSE) (see III.A.2 below).

      6) Subroutine SATEDS was streamlined w.r.t. unit number
designation and treatment.

      7) Subroutine SATEDS now keeps a count of retrievals
outside the requested time window, and prints total at end of
retrieval processing.

      8) All logic related to the processing of TOVS interactive
retrievals has been removed.

      9) Subroutine INTERP has been removed since TOVS
interactive retrievals are no longer processed.
     10) Subroutine FILLX can now include the 28 radiance values
and other ancillary data for TOVS reports (along with the 40-
level retrieval) in the printout if these are chosen to be
processed.  Printout still controlled by NAMELIST switch MODKNT.
 
     11) Reorganized and streamlined most COMMON blocks.

     12) Corrected error in encoding of initial values for
PREPBUFR header mnemonics RQM, DUP, PRG, SRC, RUC.  These are
used only by the reanalysis version of PREPDATA. (MAIN, W3FIZZ,
FIZZ01).


     
II.  SPECIFIC OPERATIONAL CHANGES


  A. CHANGES TO UPPER-AIR DATA PROCESSING

      1) The default value for namelist switch IDELEV was changed
from 20 to 30 (meters).  Since the default is used, this means
the baseline check for raobs in now more stringent (i.e., it is
now more difficult for a raob to fail the baseline check.)

      2) If the baseline check fails for a particular raob
report, any variables with an SDM keep flag already applied to
them will NOT be flagged as bad. (MAIN, GETUPA).



III.  SPECIFIC NON-OPERATIONAL CHANGES


  A. CHANGES TO TOVS SATELLITE RETRIEVAL PROCESSING

      1) GBL: Although not yet switched on, switches set to
process TOVS radiances and retrievals at full 80km resolution.

      2) GBL: Now calls W3LIB routine W3TOVUNP instead of W3FI80
to process TOVS retrievals.  Returns both 40-level retrieval
information and 28 radiances for each retrieval.  Logic in place
to save radiances and ancillary information in common block (for
later encoding into PREPBUFR).  Can process both radiances and
retrievals or just one or the other based on NAMELIST switches.
(See I.5 above.) (MAIN, SATBFR).

      3) GBL: Logic changed to now allow TOVS radiances to be
encoded in PREPBUFR file (not yet switched on). (MAIN, W3FIZZ,
FIZZ01).

      4) Added skin temperature (SKINT) to list of radiance-
ancillary information processed and encoded into PREPBUFR. (MAIN,
FILLX, W3FIZZ, FIZZ01).


   B. CHANGES TO ERS-SCATTEROMETER DATA PROCESSING

      1) Added logic to process this new data type in PREPDATA.
Processed as report type 286, and encoded into PREPBUFR data set. 
It used to be appended to PREPBUFR data set after the running of
PREPDATA.  It will not be turned on operationally until parallel
testing of the new ERS2 data is completed.  New subroutine GETERS
added.  New namelist switches JPERSD(6) (default = 6*9999) and
IEWNDO(2) (default = -3, 3) also added.  Also, logic set-up to
allow timely messages for this data to be output to IUNIT(16).  
(MAIN, PREP, W3FIZZ, FIZZ01).