Bug fix: Prevent collection duration from being shorter than frequency

History/history_mod.F90
- Added error trap to make sure that the collection duration (which
  specifies when it's time to write a new file) is never shorter than
  the collection frequency (which specifies the diagnostic time interval).
  This prevents an error that can result in empty diagnostic files.
- Updated error messages to use "YYYYMMDD hhmmss" notation

CHANGELOG.md
- UPdated accordingly

Signed-off-by: Bob Yantosca <[email protected]>

CHANGELOG.md

@@ -11,6 +11,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Added `State_Diag%Archive_SatDiagnEdgeCount` field
 - Added `State_Diag%Archive_SatDiagnEdge` field
 - Added routine `SatDiagn_or_SatDiagnEdge` in `History/history_utils_mod.F90`
+- Added error trap in `History/history_mod.F90` to ensure that collection duration is always shorter than frequency
 
 ### Changed
 - Renamed `Emiss_Carbon_Gases` to `CO2_Production` in `carbon_gases_mod.F90`

History/history_mod.F90

@@ -1223,10 +1223,37 @@ SUBROUTINE History_ReadCollectionData( Input_Opt,  State_Chm, State_Diag,  &
           ENDIF
 
           !=================================================================
-          ! At this point we are sure that the collection has been
-          ! defined, so we can continue to populate it with fields.
+          ! At this point We can assume that the collection is defined,
+          ! and that everything following are diagnostic fields.
           !=================================================================
 
+          !-----------------------------------------------------------------
+          ! ERROR CHECK: Make sure that the length of the simulation is
+          ! not shorter than the requested "File Write" interval.  This
+          ! will prevent simulations without diagnostic output.
+          !-----------------------------------------------------------------
+          IF ( CollectionDuration(C) < CollectionFrequency(C) ) THEN
+
+             ! Construct error message
+             ErrMsg =                                                        &
+                'No diagnostic output will be created for collection: "'  // &
+                 TRIM( CollectionName(C) ) // '"!  Make sure that the '   // &
+                'collection duration setting is not shorter than the '    // &
+                'collection frequency setting in HISTORY.rc!  For '       // &
+                'example, if the frequency is "00000001 000000" (1 day) ' // &
+                'but the duration is "00000000 010000" (1 hour), then '   // &
+                'this error will occur.'
+
+             ! Return error
+             WRITE( ErrorLine, 250 ) LineNum
+             CALL GC_Error( ErrMsg, RC, ThisLoc, ErrorLine )
+             RETURN
+          ENDIF
+
+          !-----------------------------------------------------------------
+          ! Continue populating the collection with fields
+          !-----------------------------------------------------------------
+
           ! Zero the counter of items
           ItemCount = 0
 
@@ -1535,9 +1562,9 @@ SUBROUTINE History_ReadCollectionData( Input_Opt,  State_Chm, State_Diag,  &
                 'length of the simulation as specified in '               // &
                 'geoschem_config.yml (check the start and end dates) is ' // &
                 'not shorter than the frequency setting in HISTORY.rc! '  // &
-                'For example, if the frequency is 010000 (1 hour) but '   // &
-                'the simulation is set up to run for only 20 minutes, '   // &
-                'then this error will occur.'
+                'For example, if the frequency is "00000000 010000" '     // &
+                '(1 hour) but the simulation is set up to run for only '  // &
+                '20 minutes, then this error will occur.'
 
              ! Return error
              WRITE( ErrorLine, 250 ) LineNum