diff --git a/.gitmodules b/.gitmodules
index 9c4aedab91..a7acd7fd08 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -28,7 +28,7 @@
[submodule "fates"]
path = src/fates
url = https://github.com/NGEET/fates
-fxtag = sci.1.79.3_api.37.0.0
+fxtag = sci.1.80.4_api.37.0.0
fxrequired = AlwaysRequired
# Standard Fork to compare to with "git fleximod test" to ensure personal forks aren't committed
fxDONOTUSEurl = https://github.com/NCAR/fates-release
diff --git a/cime_config/testdefs/ExpectedTestFails.xml b/cime_config/testdefs/ExpectedTestFails.xml
index ea25c74f64..79ead77c74 100644
--- a/cime_config/testdefs/ExpectedTestFails.xml
+++ b/cime_config/testdefs/ExpectedTestFails.xml
@@ -114,7 +114,7 @@
-
+ FAIL#1733
@@ -556,6 +556,13 @@
+
+
+ FAIL
+ #2919
+
+
+
diff --git a/cime_config/testdefs/testlist_clm.xml b/cime_config/testdefs/testlist_clm.xml
index ed6aaba0b1..200468cf53 100644
--- a/cime_config/testdefs/testlist_clm.xml
+++ b/cime_config/testdefs/testlist_clm.xml
@@ -1317,6 +1317,15 @@
+
+
+
+
+
+
+
+
+
diff --git a/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/shell_commands b/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/shell_commands
deleted file mode 100644
index e629e7ca34..0000000000
--- a/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/shell_commands
+++ /dev/null
@@ -1,8 +0,0 @@
-SRCDIR=`./xmlquery SRCROOT --value`
-CASEDIR=`./xmlquery CASEROOT --value`
-FATESDIR=$SRCDIR/src/fates
-FATESPARAMFILE=$CASEDIR/fates_params_hydrograsstempfix.nc
-
-ncgen -o $FATESPARAMFILE $FATESDIR/parameter_files/fates_params_default.cdl
-
-$FATESDIR/tools/modify_fates_paramfile.py --O --fin $FATESPARAMFILE --fout $FATESPARAMFILE --var fates_allom_smode --val 1 --allpfts
diff --git a/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/user_nl_clm b/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/user_nl_clm
index 318a34dfec..f0bdb388eb 100644
--- a/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/user_nl_clm
+++ b/cime_config/testdefs/testmods_dirs/clm/FatesColdHydro/user_nl_clm
@@ -2,7 +2,6 @@ hist_mfilt = 365
hist_nhtfrq = -24
hist_empty_htapes = .true.
use_fates_planthydro= .true.
-fates_paramfile = '$CASEROOT/fates_params_hydrograsstempfix.nc'
hist_fincl1 = 'FATES_ERRH2O_SZPF', 'FATES_TRAN_SZPF',
'FATES_SAPFLOW_SZPF', 'FATES_ITERH1_SZPF','FATES_ABSROOT_H2O_SZPF',
'FATES_TRANSROOT_H2O_SZPF','FATES_STEM_H2O_SZPF','FATES_LEAF_H2O_SZPF',
diff --git a/cime_config/testdefs/testmods_dirs/clm/flexCN_FUN_BNF/include_user_mods b/cime_config/testdefs/testmods_dirs/clm/flexCN_FUN_BNF/include_user_mods
new file mode 100644
index 0000000000..4fbf11b334
--- /dev/null
+++ b/cime_config/testdefs/testmods_dirs/clm/flexCN_FUN_BNF/include_user_mods
@@ -0,0 +1 @@
+../flexCN_FUN
diff --git a/cime_config/testdefs/testmods_dirs/clm/flexCN_FUN_BNF/user_nl_clm b/cime_config/testdefs/testmods_dirs/clm/flexCN_FUN_BNF/user_nl_clm
new file mode 100644
index 0000000000..8084f982e1
--- /dev/null
+++ b/cime_config/testdefs/testmods_dirs/clm/flexCN_FUN_BNF/user_nl_clm
@@ -0,0 +1,2 @@
+ nfix_method = 'Bytnerowicz'
+
diff --git a/doc/ChangeLog b/doc/ChangeLog
index ed6892a285..1b37b4be63 100644
--- a/doc/ChangeLog
+++ b/doc/ChangeLog
@@ -1,6 +1,235 @@
===============================================================
Tag name: ctsm5.3.017
Originator(s): slevis (Samuel Levis,UCAR/TSS,303-665-1310)
+Date: Thu 09 Jan 2025 11:56:43 AM MST
+One-line Summary: Merge tmp-241219 branch to master
+
+Purpose and description of changes
+----------------------------------
+
+Includes three tmp-241219 tags:
+ tmp-241219.n01.ctsm5.3.016 Merge b4b-dev:
+ nfix_method options Houlton (default), Bytnerowicz (option)
+ tmp-241219.n02.ctsm5.3.016 FATES hydro test update
+ tmp-241219.n03.ctsm5.3.016 Bug fix for izumi nag tests to pass (b4b unless using Bytnerowicz)
+
+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]:
+ Each separate tag documents this information below.
+
+Notes of particular relevance for users
+---------------------------------------
+Changes to CTSM's user interface (e.g., new/renamed XML or namelist variables):
+ nfix_method as explained in tmp-241219.n01.ctsm5.3.016 tag below.
+
+Notes of particular relevance for developers:
+---------------------------------------------
+Changes to tests or testing:
+ New tests as documented in tmp-241219.n03.ctsm5.3.016 tag below.
+
+Testing summary:
+----------------
+
+ regular tests (aux_clm: https://github.com/ESCOMP/CTSM/wiki/System-Testing-Guide#pre-merge-system-testing):
+
+ derecho ----- OK (baseline linked to tmp-241219.n03.ctsm5.3.016)
+ izumi ------- OK (baseline linked to tmp-241219.n03.ctsm5.3.016)
+
+ fates tests:
+ derecho ----- No new testing; last baseline is fates-sci.1.80.4_api.37.0.0-tmp-241219.n02.ctsm5.3.016
+ izumi ------- No new testing; see tmp-241219.n02.ctsm5.3.016 tag below
+
+Answer changes
+--------------
+
+Changes answers relative to baseline: Yes, only for aux_clm fates testmods
+
+ Same comment as in tmp-241219.n02.ctsm5.3.016 tag:
+ The FATES tag update includes a number of science and bug fix updates since the
+ last fates tag update, which results in non-B4B changes. These have been reviewed
+ and differ as expected.
+
+ Also, see caveat in Answer changes for tag tmp-241219.n01.ctsm5.3.016.
+
+Other details
+-------------
+List any git submodules updated (cime, rtm, mosart, cism, fates, etc.):
+ fates updated to sci.1.80.4_api.37.0.0
+
+Pull Requests that document the changes (include PR ids):
+ https://github.com/ESCOMP/ctsm/pull/2928
+
+===============================================================
+===============================================================
+Tag name: tmp-241219.n03.ctsm5.3.016
+Originator(s): slevis (Samuel Levis,UCAR/TSS,303-665-1310)
+Date: Thu 09 Jan 2025 11:39:37 AM MST
+One-line Summary: Bug fix for izumi nag tests to pass
+
+Purpose and description of changes
+----------------------------------
+ Allocation statements should have been (0:mxpft) instead of (mxpft).
+ I introduced the bug in a small refactor requested in #2917.
+
+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 #2924
+
+Notes of particular relevance for developers:
+---------------------------------------------
+Changes to tests or testing:
+ Added tests that I should have added in the tmp-241219.n01.ctsm5.3.016 tag:
+ ERP_D_Ld5_P48x1.f10_f10_mg37.I2000Clm50BgcCru.izumi_nag.clm-flexCN_FUN_BNF
+ ERP_D_Ld5_P48x1.f10_f10_mg37.I2000Clm50BgcCru.derecho_intel.clm-flexCN_FUN_BNF
+
+Testing summary:
+----------------
+ [PASS means all tests PASS; OK means tests PASS other than expected fails.]
+
+ regular tests (aux_clm: https://github.com/ESCOMP/CTSM/wiki/System-Testing-Guide#pre-merge-system-testing):
+
+ derecho ----- OK
+ izumi ------- OK
+
+If the tag used for baseline comparisons was NOT the previous tag, note that here:
+ derecho used tmp-241219.n02.ctsm5.3.016 (i.e. the previous tag)
+ izumi used ctsm5.3.016 because it was the best available baseline
+
+Answer changes
+--------------
+
+Changes answers relative to baseline: No but read caveat.
+
+ Summarize any changes to answers, i.e.,
+ - what code configurations: a few Fates cases
+ - what platforms/compilers: izumi; only because I compared to ctsm5.3.016
+ - nature of change: same as in the tmp-241219.n02.ctsm5.3.016 tag
+
+ Note: Also on izumi I see the following failure in all the tests that 'failed to initialize'
+ that I had to go back to build and run, whether with ./case.build or ./create_test. For example:
+ FAIL ERP_D_Ld5_P48x1.f10_f10_mg37.I2000Clm50BgcCru.izumi_nag.clm-noFUN_flexCN BASELINE ctsm5.3.016: ERROR CPRNC failed to open files
+ I am aware that others have also seen this behavior.
+
+Other details
+-------------
+Pull Requests that document the changes (include PR ids):
+ https://github.com/ESCOMP/ctsm/pull/2925
+
+===============================================================
+===============================================================
+Tag name: tmp-241219.n02.ctsm5.3.016
+Originator(s): glemieux (Gregory Lemieux, LBNL, glemieux@lbl.gov)
+Date: Wed 08 Jan 2025 10:52:49 AM MST
+One-line Summary: FATES hydro test update
+
+Purpose and description of changes
+----------------------------------
+
+This minor update reverts a temporary work around for FATES hydro system tests.
+The FATES tag is updated to capture the FATES-side fix to the issue that predicated
+the temporary testing workaround.
+
+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]:
+
+ #2878 - Remove fates_allom_smode shell_command update in FatesColdHydro testmod
+
+Notes of particular relevance for developers:
+---------------------------------------------
+Changes to tests or testing:
+ FATES hydro tests will no long build a custom parameter file on the fly
+ The one FATES PVT test has been added to expected failure per #2919
+
+Testing summary: regular + fates
+----------------
+ [PASS means all tests PASS; OK means tests PASS other than expected fails.]
+
+ regular tests (aux_clm: https://github.com/ESCOMP/CTSM/wiki/System-Testing-Guide#pre-merge-system-testing):
+
+ derecho ----- OK
+ izumi ------- OK (see #2924)
+
+ fates tests: (give name of baseline if different from CTSM tagname, normally fates baselines are fates--)
+ derecho ----- OK
+ izumi ------- OK
+
+
+Answer changes
+--------------
+
+Changes answers relative to baseline: Yes, but only for aux_clm fates testmods
+
+ The FATES tag update includes a number of science and bug fix updates since the
+ last fates tag update, which results in non-B4B changes. These have been reviewed
+ and differ as expected.
+
+Other details
+-------------
+List any git submodules updated (cime, rtm, mosart, cism, fates, etc.):
+ fates: sci.1.79.3_api.37.0.0 -> sci.1.80.4_api.37.0.0
+
+Pull Requests that document the changes (include PR ids):
+(https://github.com/ESCOMP/ctsm/pull)
+ https://github.com/ESCOMP/CTSM/pull/2882
+
+===============================================================
+===============================================================
+Tag name: tmp-241219.n01.ctsm5.3.016
+Originator(s): slevis (Samuel Levis,UCAR/TSS,303-665-1310)
Date: Tue 24 Dec 2024 03:43:01 PM MST
One-line Summary: Merge b4b-dev
diff --git a/doc/ChangeSum b/doc/ChangeSum
index 60d46392ff..545a02ff25 100644
--- a/doc/ChangeSum
+++ b/doc/ChangeSum
@@ -1,6 +1,9 @@
Tag Who Date Summary
============================================================================================================================
- ctsm5.3.017 slevis 12/24/2024 Merge b4b-dev
+ ctsm5.3.017 slevis 01/09/2025 Merge tmp-241219 branch to master
+tmp-241219.n03.ctsm5.3.016 01/09/2025 Bug fix for izumi nag tests to pass (slevis)
+tmp-241219.n02.ctsm5.3.016 01/08/2025 FATES hydro test update (glemieux)
+tmp-241219.n01.ctsm5.3.016 12/24/2024 Merge b4b-dev (slevis)
ctsm5.3.016 erik 12/19/2024 Rpointer files for restart now have the simulation date in the filename
ctsm5.3.015 erik 12/18/2024 Update cdeps with cam7 nextsw cday changes
ctsm5.3.014 erik 12/03/2024 Bring in several fixes for testing in the previous cesm3_0_beta03/04 tags
diff --git a/src/fates b/src/fates
index e3e7d2cd86..296e1d6a45 160000
--- a/src/fates
+++ b/src/fates
@@ -1 +1 @@
-Subproject commit e3e7d2cd86a66f8ca0e8f6dc4a823246a2bdb95b
+Subproject commit 296e1d6a45f05a800073d376286d0537d2290e96