FIXISHD                         April 11, 2007
                                        
                              Utility Program for AERMET


Problems have been reported with AERMET processing of some data files in the Integrated 
Surface Hourly Data (ISHD) format, also called TD-3505.  The current AERMET program
(dated 06341) aborts during Stage 1 processing in these cases, with a runtime error 
generated from subroutine RDISHD.  This has been traced to a potential problem with the 
format of some ISHD data files, which lack a delimiter ('EQD') used by AERMET to identify 
the extent of usable data within the variable length portion of the ISHD data records.  
Without the 'EQD' delimiter, AERMET attempts to process an invalid data field with the 
'GA1' code.  EPA has reported this issue to the National Climatic Data Center (NCDC), 
and will revise the AERMET program as appropriate based on the results of these discussions.

A utility program, called FIXISHD, has been developed that will identify and replace records 
with this formatting problem in an ISHD data file, inserting a delimiter of 'EQDEPA' in the 
appropriate place to allow AERMET to successfully process the data file.  The 'EQDEPA' 
delimiter will also serve to uniquely identify these records for future reference.

The FIXISHD program can be run from a command prompt and will prompt the user for the 
name of the input (unmodified) ISHD data file and the output (modified) data file.  The 
FIXISHD program will automatically generate a log file, called 'fixishd.log', containing the 
original and modified data for each record replaced.  This utility program is being released 
as an interim fix to this problem until an update to the AERMET program can be released.

The fixishd.zip file contains the Fortran source code and executable for the FIXISHD program, 
and sample input, output and log files for 2001 ISHD data from Bridgeport, CT.