diff --git a/cicecore/cicedyn/general/ice_init.F90 b/cicecore/cicedyn/general/ice_init.F90
index 62a46e2cb..6313ffb37 100644
--- a/cicecore/cicedyn/general/ice_init.F90
+++ b/cicecore/cicedyn/general/ice_init.F90
@@ -325,7 +325,7 @@ subroutine input_data
       histfreq_base = 'zero' ! output frequency reference date
       hist_avg(:) = .true.   ! if true, write time-averages (not snapshots)
       history_format = 'default' ! history file format
-      hist_time_axis = 'end' ! History file time axis interval position
+      hist_time_axis = 'end' ! History file time axis averaging interval position
 
       history_dir  = './'    ! write to executable dir for default
       history_file = 'iceh'  ! history file name prefix
diff --git a/cicecore/cicedyn/infrastructure/io/io_netcdf/ice_history_write.F90 b/cicecore/cicedyn/infrastructure/io/io_netcdf/ice_history_write.F90
index 2f543bbd2..4134b5d3b 100644
--- a/cicecore/cicedyn/infrastructure/io/io_netcdf/ice_history_write.F90
+++ b/cicecore/cicedyn/infrastructure/io/io_netcdf/ice_history_write.F90
@@ -750,6 +750,8 @@ subroutine ice_write_hist (ns)
        
         ltime2 = timesecs/secday ! hist_time_axis = 'end' (default)
 
+        ! Some coupled models require the time axis "stamp" to be in the middle
+        ! or even beginning of averaging interval.
         if (hist_avg(ns)) then
            if (trim(hist_time_axis) == "begin" ) ltime2 = time_beg(ns)
            if (trim(hist_time_axis) == "middle") ltime2 = p5*(time_beg(ns)+time_end(ns))
diff --git a/cicecore/cicedyn/infrastructure/io/io_pio2/ice_history_write.F90 b/cicecore/cicedyn/infrastructure/io/io_pio2/ice_history_write.F90
index a92326c58..1cd0e1188 100644
--- a/cicecore/cicedyn/infrastructure/io/io_pio2/ice_history_write.F90
+++ b/cicecore/cicedyn/infrastructure/io/io_pio2/ice_history_write.F90
@@ -706,6 +706,8 @@ subroutine ice_write_hist (ns)
 
         ltime2 = timesecs/secday ! hist_time_axis = 'end' (default)
 
+        ! Some coupled models require the time axis "stamp" to be in the middle
+        ! or even beginning of averaging interval.
         if (hist_avg(ns)) then
            if (trim(hist_time_axis) == "begin" ) ltime2 = time_beg(ns)
            if (trim(hist_time_axis) == "middle") ltime2 = p5*(time_beg(ns)+time_end(ns))
diff --git a/doc/source/user_guide/ug_implementation.rst b/doc/source/user_guide/ug_implementation.rst
index 69cae5bcf..f6327333c 100644
--- a/doc/source/user_guide/ug_implementation.rst
+++ b/doc/source/user_guide/ug_implementation.rst
@@ -1200,7 +1200,8 @@ or averaged as specified by the ``hist_avg`` namelist setting and the frequency
 will be relative to a reference date specified by ``histfreq_base``.  Also, some
 Earth Sytem Models require the history file time axis to be centered in the averaging
 interval. The flag ``hist_time_axis`` will allow the user to chose ``begin``, ``middle``,
-or ``end``. More information about how the frequency is computed is found in :ref:`timemanager`.
+or ``end`` for the time stamp. More information about how the frequency is 
+computed is found in :ref:`timemanager`.
 
 For example, in the namelist: