Improve cycle cadence specification in CROW

Replaces the old gfs_cyc method for determining cycling frequency with one that
explicitly sets the step length. In place of gfs_cyc there are two new variables
to determine step sizing: STEP_GFS and STEP_DA. Both are of the timedelta type.

STEP_GFS determines the frequency of GFS and defaults to 6 hours
STEP_DA determines the frequency of DA and also defaults to 6 hours

If STEP_GFS is set to 00:00:00, only the DA system is run
If STEP_DA is set to 00:00:00, only the GFS system is run (free-forecast mode)

Note that this new method currently requires the additional setting of STEP_DA
to zero, in addition to using free forecast layout.

If STEP_DA is non-zero, the first cycle is DA-only, so this should be kept in
mind when setting up your experiments (especially if you want GFS to run at
certain times of day). If both are non-zero, STEP_GFS should always be an
integer multiple of STEP_DA, otherwise unexpected behavior may occur. Other
than setting STEP_DA to zero for free forecast, STEP_DA is unlikely to be
changed from its default value in the near-future for GFS, but the new method
is flexible for any future incorporation of LAM system that requires faster DA
cycling.

Examples:

Full-cycling with DA & GFS:
STEP_GFS: !timedelta "06:00:00"
STEP_DA: !timedelta "06:00:00"
(since these are defaults, nothing needs to be placed in the case file, but you may
wish to for clarity)

Normal DA with GFS at each 00z starting 2013-04-01:
SDATE: 2013-03-31t18:00:00
STEP_GFS: !timedelta "24:00:00"

Free forecast with GFS every 24h at 00z starting 2013-04-01:
SDATE: 2013-04-01t00:00:00
STEP_GFS: !timedelta "24:00:00"
STEP_DA: !timedelta "00:00:00"

CROW ss updated to add a new tool that converts a timedelta to a string.

The wave model, which formerly used gfs_cyc to determine the wave cycling interval,
now determines WAVHCYC directly from STEP_GFS. Since this variable is only a number
of hours, this will only work for whole-hour GFS frequencies.

Case files have been updated to use the new settings in place of gfs_cyc, as well as
set STEP_DA to zero for free forecast cases. However, they have not all been tested.

Additional testing is needed to ensure these changes are fully operational for DA
cycling runs.

Refs: NOAA-EMC#260, NOAA-EMC#314

workflow/cases/aerosol_firex_forecast.yaml

@@ -11,10 +11,10 @@ case:
   settings: 
     SDATE: 2019-07-01t00:00:00
     EDATE: 2019-07-15t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
     max_job_tries: 1
 
-    gfs_cyc: 1
-
     cplgocart: .true.
     print_esmf: .true.
     nems_temp: 'atm_aer'

workflow/cases/aerosol_free_forecast.yaml

@@ -4,8 +4,11 @@ case:
 
   settings: 
     SDATE: 2013-04-01t00:00:00
-    EDATE: 2013-04-01t00:00:00
+    EDATE: 2013-04-02t00:00:00    
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
     max_job_tries: 1
+    rocoto_cycle_throttle: 1
 
     cplgocart: .true.
     print_esmf: .true.
@@ -35,12 +38,12 @@ case:
     LEVS: 65
     DELTIM: 450
     layout:
-       x: 6
-       y: 8
-       nth: 1
-       WGRP: 1
-       WGRP_NTASKS: 24
-       WRTIOBUF: "32M"
+      x: 6
+      y: 8
+      nth: 1
+      WGRP: 1
+      WGRP_NTASKS: 24
+      WRTIOBUF: "32M"
 
   chem_settings:
     MOD: gsdchem
@@ -55,3 +58,6 @@ case:
   post:
     downset: 2
     GOESF: no
+
+  archiving:
+    archive_to_hpss: False

workflow/cases/atm_free_forecast.yaml

@@ -6,6 +6,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     cplflx: .false.
     print_esmf: .true.

workflow/cases/coupled_free_forecast.yaml

@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_frac

workflow/cases/coupled_free_forecast_nofrac_wave.yaml

@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_orig

workflow/cases/coupled_free_forecast_wave.yaml

@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_frac

workflow/cases/dev/Run-From-HPSS-ICs.yaml

@@ -57,10 +57,7 @@ case:
     # files instead.
     chgres_and_convert_ics: yes
 
-    # gfs_cyc: this setting is used in a full data assimilation cycled
-    # workflow to only run the GFS every N cycles.  Keep this at "4" to
-    # ensure it is run every cycle.  
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
 
   places:
     # workflow_file: which workflow we're running.  This specifies the

workflow/cases/dev/ecrealtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml

@@ -136,5 +136,5 @@ case:
     EDATE: 2018-08-30t18:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/four_cycle_mode_prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml

@@ -141,7 +141,7 @@ case:
     EDATE: 2018-08-10t18:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
   schedvar:

workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM-Dell.yaml

@@ -134,5 +134,5 @@ case:
     EDATE: 2016-04-18t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM.yaml

@@ -172,5 +172,5 @@ case:
     EDATE: 2016-05-31t18:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_fixed.yaml

@@ -186,5 +186,5 @@ case:
     EDATE: 2016-02-14t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ENKF@384+80MEM_whatever.yaml

@@ -186,5 +186,5 @@ case:
     EDATE: 2016-02-14t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/fv3q2fy19retro5-GFS@C768_ff_fixed.yaml

@@ -95,5 +95,6 @@ case:
     EDATE: 2016-02-14t12:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
     run_gsi: No

workflow/cases/dev/gaea-test.yaml

@@ -21,5 +21,5 @@ case:
     SDATE: 2015-11-26t00:00:00
     EDATE: 2015-11-26t00:00:00
     realtime: false
-    gfs_cyc: 4 # run gfs four cycles a day
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: No # disable data assimilation

workflow/cases/dev/lowrsecf@C384.yaml

@@ -31,7 +31,7 @@ case:
     EDATE: 2018-05-31t12:00:00
     chgres_and_convert_ics: No
     REALTIME: true
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: YES
 
   post:

workflow/cases/dev/merge2dell_baseline.yaml

@@ -139,7 +139,7 @@ case:
     EDATE: 2018-11-26t12:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
   schedvar:

workflow/cases/dev/merge2jet_baseline.yaml

@@ -181,5 +181,5 @@ case:
     EDATE: 2019-05-02t00:00:00
     chgres_and_convert_ics: No
     realtime: false
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/nco.yaml

@@ -136,7 +136,7 @@ case:
     EDATE: 2018-09-22t06:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 
   schedvar:

workflow/cases/dev/parallel@768_ENKF@384+80MEM.yaml

@@ -34,7 +34,7 @@ case:
     IC_CDUMP: gdas # Get initial conditions from 1st cycle from GFS or GDAS
     SDATE: 2018-05-03t00:00:00
     EDATE: 2018-05-03t18:00:00
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
     chgres_and_convert_ics: No
 

workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM-Dell.yaml

@@ -119,5 +119,5 @@ case:
     EDATE: 2018-09-09t18:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes

workflow/cases/dev/realtime-prfv3rt1_GFS@C768_ENKF@384+80MEM.yaml

@@ -42,6 +42,6 @@ case:
     EDATE: 2018-06-04t12:00:00
     chgres_and_convert_ics: No
     realtime: true
-    gfs_cyc: 4 # run gfs at 0z, 12z
+    STEP_GFS: !timedelta "06:00:00"
     run_gsi: Yes
 

workflow/cases/free_forecast_case.yaml

@@ -9,10 +9,11 @@ case:
   settings: 
     SDATE: 2019-05-01t00:00:00
     EDATE: 2019-05-01t06:00:00
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     DUMP_SUFFIX: "p"
     run_gsi: No
     chgres_and_convert_ics: Yes
-    gfs_cyc: 4 # run gfs every cycle
 
     mom6ic_prepared: .true.

workflow/cases/jet_cycled.yaml

@@ -16,4 +16,4 @@ case:
     DUMP_SUFFIX: ""
     run_gsi: Yes
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/jet_free_forecast.yaml

@@ -14,11 +14,12 @@ case:
   settings: 
     SDATE: 2019-05-01t00:00:00
     EDATE: 2019-05-01t00:00:00
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     DUMP_SUFFIX: "p"
     run_gsi: No
     chgres_and_convert_ics: Yes
-    gfs_cyc: 4 # run gfs every cycle
 
   suite_overrides: !FirstTrue
     - when: !calc (doc.platform.name=="JET")

workflow/cases/manual_mode.yaml

@@ -92,7 +92,7 @@ case:
     DUMP_SUFFIX: "p"
     run_gsi: Yes
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
 
   downstream: &downstream
     DO_POST_PROCESSING: NO

workflow/cases/prototype6.yaml

@@ -5,6 +5,8 @@ case:
   settings: 
     SDATE: 2013-04-01t00:00:00
     EDATE: 2013-04-01t00:00:00
+    STEP_GFS: !timedelta "24:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     onestep: .true.
     cplmode: nems_frac

workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C192.yaml

@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/AtmRiv_2016021000_GFS@C384.yaml

@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/Harvey_2017081712_GFS@C192.yaml

@@ -19,4 +19,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384-override-stuff-in-case-file.yaml

@@ -19,7 +19,7 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"
 
   suite_overrides: !FirstTrue
     - when: !calc (doc.platform.name=="JET")

workflow/cases/public_release_v1/Harvey_2017081712_GFS@C384.yaml

@@ -19,4 +19,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/Harvey_2017081712_GFS@C768.yaml

@@ -19,4 +19,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C192.yaml

@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C384.yaml

@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/public_release_v1/March_Noreasters_2018022800_GFS@C768.yaml

@@ -17,4 +17,4 @@ case:
     IC_CDUMP: gfs
     run_gsi: No
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/tutorial_cycled.yaml

@@ -17,4 +17,4 @@ case:
     KEEPDATA: Yes
     run_gsi: Yes
     chgres_and_convert_ics: No
-    gfs_cyc: 4 # run gfs every cycle
+    STEP_GFS: !timedelta "06:00:00"

workflow/cases/tutorial_free_forecast.yaml

@@ -9,11 +9,12 @@ case:
   settings: 
     SDATE: 2019-05-01t00:00:00
     EDATE: 2019-05-01t06:00:00
+    STEP_GFS: !timedelta "06:00:00"
+    STEP_DA: !timedelta "00:00:00"
 
     DUMP_SUFFIX: "p"
     run_gsi: No
     chgres_and_convert_ics: Yes
-    gfs_cyc: 4 # run gfs every cycle
 
   suite_overrides: !FirstTrue
     - when: !calc (doc.platform.name=="JET")

workflow/config/base.yaml

@@ -191,10 +191,7 @@ config_base:
     export FHMIN={doc.output_settings.FHMIN_GDAS}
     export FHMAX={doc.output_settings.FHMAX_GDAS}
     export FHOUT={doc.output_settings.FHOUT_GDAS}
-    
-    # GFS cycle info
-    export gfs_cyc={doc.settings.gfs_cyc} # 0: no GFS cycle, 1: 00Z only, 2: 00Z and 12Z only, 4: all 4 cycles.
-    
+        
     # GFS output and frequency
     export FHMIN_GFS={doc.output_settings.FHMIN_GFS}
     export FHMAX_GFS={doc.output_settings.FHMAX_GFS}

workflow/config/wave.yaml

@@ -78,12 +78,8 @@ config_wave:
         WAVNCYC=4
         WAVHCYC=6
         FHMAX_WAV_CUR=48 # RTOFS forecasts only out to 8 days
-      elif [ $gfs_cyc -ne 0 ]
-      then
-        FHMAX_WAV_CUR=192 # RTOFS forecasts only out to 8 days
-        WAVHCYC=`expr 24 / $gfs_cyc`
       else
-        WAVHCYC=0
+        WAVHCYC={tools.dt_to_HMS(doc.settings.STEP_GFS).split(':')[0]}
         FHMAX_WAV_CUR=192 # RTOFS forecasts only out to 8 days
       fi
       export FHMAX_WAV_CUR WAVHCYC WAVNCYC

workflow/defaults/settings.yaml

@@ -35,7 +35,6 @@ default_settings: &default_settings
   ecflow_virtual_clock: no
   ecflow_hybrid_clock: no
 
-  gfs_cyc: 4
   nems_temp: 'atm'
   nems_temp_cold: 'atm'
   ics_from: opsgfs
@@ -78,6 +77,9 @@ default_settings: &default_settings
   IAUFHRS: 6
   IAU_DELTHRS: 6
 
+  STEP_DA: !timedelta "06:00:00"
+  STEP_GFS: !timedelta "06:00:00"
+
   KEEPDATA: NO
   DUMP_SUFFIX: ""
   run_gsi: No