ctsm5.4.020: Update namelist defaults: paramfile, rh_hgh, defo_fire_precip_thresh_bet, initial conditions

bld/namelist_files/namelist_defaults_ctsm.xml

@@ -335,7 +335,6 @@ attributes from the config_cache.xml file (with keys converted to upper-case).
 <nonborpeat_fire_precip_denom>1.0d00</nonborpeat_fire_precip_denom>
 
 <defo_fire_precip_thresh_bet>4.0d00</defo_fire_precip_thresh_bet>
-<defo_fire_precip_thresh_bet fire_method="li2024crujra">3.0d00</defo_fire_precip_thresh_bet>
 
 <rh_low                   fire_method="li2014qianfrc" >30.0d00</rh_low>
 <rh_hgh                   fire_method="li2014qianfrc" >80.0d00</rh_hgh>
@@ -452,6 +451,7 @@ attributes from the config_cache.xml file (with keys converted to upper-case).
 
 <rh_low                   fire_method="li2024crujra" >30.0d00</rh_low>
 <rh_hgh                   fire_method="li2024crujra" >85.0d00</rh_hgh>
+<rh_hgh                   fire_method="li2024crujra" lnd_tuning_mode="clm6_0_cam7.0">80.0d00</rh_hgh>
 <bt_min                   fire_method="li2024crujra" >0.85d00</bt_min>
 <bt_max                   fire_method="li2024crujra" >0.98d00</bt_max>
 <cli_scale                fire_method="li2024crujra" >0.03d00</cli_scale>
@@ -465,7 +465,8 @@ attributes from the config_cache.xml file (with keys converted to upper-case).
 <cmb_cmplt_fact_litter    fire_method="li2024crujra" >0.5d00</cmb_cmplt_fact_litter>
 <cmb_cmplt_fact_cwd       fire_method="li2024crujra" >0.28d00</cmb_cmplt_fact_cwd>
 <max_rh30_affecting_fuel  fire_method="li2024crujra" >95.</max_rh30_affecting_fuel>
-<defo_fire_precip_thresh_bet fire_method="li2024crujra" >1.8d00</defo_fire_precip_thresh_bet>
+<defo_fire_precip_thresh_bet fire_method="li2024crujra" >3.0d00</defo_fire_precip_thresh_bet>
+<defo_fire_precip_thresh_bet fire_method="li2024crujra" lnd_tuning_mode="clm6_0_cam7.0">1.4d00</defo_fire_precip_thresh_bet>
 <defo_fire_precip_thresh_bdt fire_method="li2024crujra" >0.6d00</defo_fire_precip_thresh_bdt>
 <borpeat_fire_soilmoist_denom fire_method="li2024crujra" > 0.3d00</borpeat_fire_soilmoist_denom>
 <nonborpeat_fire_precip_denom fire_method="li2024crujra" >6.5d00</nonborpeat_fire_precip_denom>
@@ -622,7 +623,8 @@ attributes from the config_cache.xml file (with keys converted to upper-case).
 <!-- The default filenames are given relative to the root directory
      for the CLM2 data in the CESM distribution -->
 <!-- Plant function types (relative to {csmdata}) -->
-<paramfile phys="clm6_0" >lnd/clm2/paramdata/ctsm60_params.c260108.nc</paramfile>
+<paramfile phys="clm6_0" >lnd/clm2/paramdata/ctsm60_params.c260204.nc</paramfile>
+<paramfile phys="clm6_0" lnd_tuning_mode="clm6_0_cam7.0">ctsm60-cam70_params.c260204.nc</paramfile>
 <paramfile phys="clm5_0" >lnd/clm2/paramdata/clm50_params.c250311.nc</paramfile>
 <paramfile phys="clm4_5" >lnd/clm2/paramdata/clm45_params.c250311.nc</paramfile>
 
@@ -1456,7 +1458,7 @@ attributes from the config_cache.xml file (with keys converted to upper-case).
          sim_year="1850" do_transient_pfts=".false." use_excess_ice=".true."
          use_crop=".true."
          phys="clm6_0"
->lnd/clm2/initdata_esmf/ctsm5.4/ctsm5.4.CMIP7_ciso_ctsm5.4.004_bgc_ne30_130_pSASU_greenland.clm2.r.0121-01-01-00000.nc
+>lnd/clm2/initdata_esmf/ctsm5.4/ctsm5.4.015_BGCcrop_ne30_144_pSASU.clm2.r.0181-01-01-00000.nc
 </finidat>
 <!-- Corresponding f19 -->
 <finidat hgrid="1.9x2.5" mask="tx2_3v2" use_cn=".true." use_cndv=".false." use_fates=".false."

doc/ChangeLog

@@ -1,4 +1,95 @@
 ===============================================================
+Tag name: ctsm5.4.020
+Originator(s): slevis (Samuel Levis,UCAR/TSS,303-665-1310)
+Date: Thu Feb 19 08:28:59 AM MST 2026
+One-line Summary: Address carbon cycle and fire biases in CESM3 development runs by updating namelist defaults
+
+Purpose and description of changes
+----------------------------------
+
+ - New defaults for lnd_tuning_mode="clm6_0_cam7.0"
+ defo_fire_precip_thresh_bet = 1.4d00
+ rh_hgh = 80.0d00
+
+ - New default paramfiles
+ for clm6: /glade/work/linnia/CLM6-PPE/ctsm6_cal/paramfiles/ctsm60_params.c260204.nc
+ for lnd_tuning_mode="clm6_0_cam7.0": /glade/u/home/slevis/paramfiles/iss3725_forFang/ctsm60_params.c260204.cesm3-01.nc
+ The latter got renamed to ctsm60-cam70_params.c260204.nc and it increases pft-specific values of "rswf_max" and "rswf_min"
+
+ - New default finidat for ne30 and 1850
+ /glade/derecho/scratch/wwieder/archive/ctsm5.4.015_BGCcrop_ne30_144_pSASU/rest/0181-01-01-00000/ctsm5.4.015_BGCcrop_ne30_144_pSASU.clm2.r.0181-01-01-00000.nc
+
+ All new files got moved to /inputdata and got rimported.
+
+Significant changes to scientifically-supported configurations
+--------------------------------------------------------------
+
+Does this tag change answers significantly for any of the following physics configurations?
+(Details of any changes will be given in the "Answer changes" section below.)
+
+    [Put an [X] in the box for any configuration with significant answer changes.]
+
+[ ] clm6_0
+
+[ ] clm5_0
+
+[ ] ctsm5_0-nwp
+
+[ ] clm4_5
+
+
+Bugs fixed
+----------
+List of CTSM issues fixed (include CTSM Issue # and description) [one per line]:
+ Fixes #3725
+
+Notes of particular relevance for users
+---------------------------------------
+Changes made to namelist defaults (e.g., changed parameter values):
+ Listed above.
+
+Changes to the parameter file (output of tools/param_utils/compare_paramfiles):
+ Listed above.
+
+Changes to documentation:
+ Not, yet.
+
+Testing summary:
+----------------
+
+ [PASS means all tests PASS; OK means tests PASS other than expected fails.]
+
+  build-namelist tests (if CLMBuildNamelist.pm has changed):
+
+    derecho - OK (2 expected fails)
+
+  regular tests (aux_clm: https://github.com/ESCOMP/CTSM/wiki/System-Testing-Guide#pre-merge-system-testing):
+
+    derecho ----- OK
+    izumi ------- OK
+
+Answer changes
+--------------
+
+Changes answers relative to baseline: Yes
+
+  Summarize any changes to answers, i.e.,
+    - what code configurations: Clm6
+    - what platforms/compilers: all
+    - nature of change: larger than roundoff due to changes in defaults
+
+   If this tag changes climate list the run(s) done to evaluate the new
+   climate. Preferably in https://github.com/NCAR/LMWG_dev (or give details below)
+       - LMWG_dev issue number(s): https://github.com/NCAR/LMWG_dev/issues/141
+                                   https://github.com/NCAR/LMWG_dev/issues/143
+
+Other details
+-------------
+Pull Requests that document the changes (include PR ids):
+ https://github.com/ESCOMP/ctsm/pull/3756
+
+===============================================================
+===============================================================
 Tag name: ctsm5.4.019
 Originator(s): samrabin (Sam Rabin, UCAR/TSS)
 Date: Thu Feb 12 16:21:47 MST 2026

doc/ChangeSum

@@ -1,5 +1,6 @@
 Tag                   Who      Date  Summary
 ============================================================================================================================
+       ctsm5.4.020   slevis 02/19/2026 Address carbon cycle and fire biases in CESM3 development runs by updating namelist defaults
        ctsm5.4.019 samrabin 02/12/2026 Fix years used by generate_gdds
        ctsm5.4.018     erik 02/12/2026 Quick fix so that we can use Nitrogen Deposition sent from the ATM model
        ctsm5.4.017   slevis 02/09/2026 Introduce CRUJRA2024b datm option (Greenand snow hole filled)