                        Model Change Bulletin

                                MCB#7                       04/22/2021

                        AERSCREEN (dated 21112)

This Model Change Bulletin (MCB) documents changes made to the AERSCREEN 
screening model.  A brief description of the changes is provided below. 
Additional details are available in the FORTRAN source code and in 
the AERSCREEN user's guide.


This revised version of AERSCREEN (dated 21112) includes the following
modifications relative to the previous version (16216):


Miscellaneous

1.  Move the logic statement to reset of maximum shoreline 
    concentration to zero to within logic code checking that
    chi is greater than shorechi in SHOREMAX.
2.  Modified subroutine SHOREMAX to output a message to the debug 
    file if the distance to shore for the maximum concentration is
    less than 200 m, that the concentration is set to 0.

Bug Fixes
1.  Added code to set chi to zero if distance to maximum concentration
    is less than 2 km in INVMAX for inversion break-up fumigation.
2.  Initialize ldefault to .TRUE. in INITPROMPTS so that AERSCREEN
    does not try to write to a non-default log filename if AERSCREEN
    aborts prior to determining if non-default names are used.
    