Model Change Bulletin

                                  MCB#5                          06/04/99

                            MPRM (dated 99155)


     This Model Change Bulletin implements changes to the Meteorological
Processor for Regulatory Models (MPRM) associated with the gas dry
deposition algorithm incorporated into the ISCST3 model (dated 99155).

     These changes constitute MPRM (dated 99155).  With this bulletin the
source code and executables for MPRM (dated 99155) are being made available
for downloading from the 'Models / Related Programs' area of SCRAM.  MPRM
(dated 99155) replaces MPRM (dated 96225) and the draft gas dry deposition
version [GDMPRDFT (dated 96248)].  These old versions are obsolete and,
with this bulletin, will no longer be available on SCRAM.

     Details regarding the revisions to the user interface for MPRM can be
found in the Addendum to the MPRM User's Guide (EPA-454/B-96-002).  The
user's guide addendum is available for downloading from the 'User's
Guide / Related Programs' area of SCRAM.

     The modifications to MPRM are summarized in the following:

1.   Additional Parameters for Gas Dry Deposition - MPRM has been modified
     to process additional parameters for use in the gas dry deposition
     algorithm of the ISCST3 model (dated 99155).  The ISCGASD and ISCGASW
     model options require the additional input of lead area index (LAI)
     on the surface characteristics card in Stage 3.  The incoming short-
     wave radiation and LAI are also included on each record of the output
     meteorological file.


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    This program will henceforth be identified by its name and a Julian date,
i.e.: MPRM (dated 99155).  Future changes to this program will be identified
by an updated Julian date found at the beginning of the program source code
and followed by a reference to a SCRAM Model Change Bulletin (MCB#n)
which will explain the nature and content of the changes.  All Model Change
Bulletins for this program will always be available for back reference on
this website.  In the future, notification of changes (MCBs) to this program
will be made in the SCRAM ALERTS section of this website.