diff --git a/CHANGELOG.md b/CHANGELOG.md
index eaeb459db..fa24a886d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -370,6 +370,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 ## [14.2.1] - 2023-10-10
 ### Added
+- Added option to run GEOS-Chem at 0.125x0.15625 resolution using GEOS-FP derived winds fields generated from c720 mass fluxes archived by GMAO
+
+## [Unreleased 14.2.1] - TBD
+### Added
 - Script `test/difference/diffTest.sh`, checks 2 different integration tests for differences
 - Added GCHP environment file and export/unset env variables in run script for NASA Pleiades cluster
 `SatDiagnEdge` collection to all GEOS-Chem Classic `HISTORY.rc` templates
diff --git a/GeosCore/flexgrid_read_mod.F90 b/GeosCore/flexgrid_read_mod.F90
index 93ea8cbc0..7811a2cbb 100644
--- a/GeosCore/flexgrid_read_mod.F90
+++ b/GeosCore/flexgrid_read_mod.F90
@@ -34,10 +34,14 @@ MODULE FlexGrid_Read_Mod
 !
   PUBLIC  :: FlexGrid_Read_CN
   PUBLIC  :: FlexGrid_Read_A1
+  PUBLIC  :: FlexGrid_Read_A1dyn
   PUBLIC  :: FlexGrid_Read_A3
+  PUBLIC  :: FlexGrid_Read_I1dyn_1
+  PUBLIC  :: FlexGrid_Read_I1dyn_2
   PUBLIC  :: FlexGrid_Read_I3_1
   PUBLIC  :: FlexGrid_Read_I3_2
   PUBLIC  :: Copy_I3_Fields
+  PUBLIC  :: Copy_I1dyn_Fields
 !
 ! !REMARKS:
 !  Assumes that you have a netCDF library (either v3 or v4) installed on
@@ -546,6 +550,143 @@ END SUBROUTINE FlexGrid_Read_A1
 !------------------------------------------------------------------------------
 !BOP
 !
+! !IROUTINE: FlexGrid_Read_a1dyn
+!
+! !DESCRIPTION: Routine to read variables and attributes from a NetCDF
+!  met fields file containing 1-hr time-averaged (A1) data.
+!\\
+!\\
+! !INTERFACE:
+!
+  SUBROUTINE FlexGrid_Read_A1dyn( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
+                                  State_Met )
+!
+! !USES:
+!
+    USE Input_Opt_Mod,      ONLY : OptInput
+    USE State_Grid_Mod,     ONLY : GrdState
+    USE State_Met_Mod,      ONLY : MetState
+    USE Get_Met_Mod
+!
+! !INPUT PARAMETERS:
+!
+    INTEGER,        INTENT(IN)    :: YYYYMMDD   ! GMT date in YYYY/MM/DD format
+    INTEGER,        INTENT(IN)    :: HHMMSS     ! GMT time in hh:mm:ss   format
+    TYPE(OptInput), INTENT(IN)    :: Input_Opt  ! Input Options object
+    TYPE(GrdState), INTENT(IN)    :: State_Grid ! Grid State object
+!
+! !INPUT/OUTPUT PARAMETERS:
+!
+    TYPE(MetState), INTENT(INOUT) :: State_Met  ! Meteorology State object
+!
+! !REMARKS:
+!  This routine was automatically generated by the Perl script ncCodeRead,
+!  and was subsequently hand-edited for compatibility with GEOS-Chem.
+!                                                                             .
+!  Even though the netCDF file is self-describing, the GEOS-FP data,
+!  dimensions, and units are pre-specified according to the GMAO GEOS-FP
+!  file specification.  Therefore we can "cheat" a little bit and not have
+!  to read netCDF attributes to find what these values are.
+!                                                                             .
+!  Special handling for surface precipitation fields:
+!  ---------------------------------------------------------------------------
+!  In GEOS-FP (and in MERRA), the PRECTOT etc. surface precipitation
+!  met fields fields have units of [kg/m2/s].  In all other GEOS
+!  versions, PREACC and PRECON have units of [mm/day].
+!                                                                             .
+!  Therefore, for backwards compatibility with existing code, apply
+!  the following unit conversion to the GEOS-5 PRECTOT and PRECCON
+!  fields:
+!                                                                             .
+!      kg  |    m3    | 86400 s | 1000 mm
+!    ------+----------+---------+--------- = 86400
+!     m2 s |  1000 kg |  day    |   m
+!               ^
+!               |
+!        1 / density of water
+!
+! !REVISION HISTORY:
+!  30 Jan 2012 - R. Yantosca - Initial version
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+! !LOCAL VARIABLES:
+!
+    ! Scalars
+    INTEGER            :: t_index            ! Time index
+    CHARACTER(LEN=16)  :: stamp              ! Time and date stamp
+    CHARACTER(LEN=255) :: v_name             ! netCDF variable name
+    CHARACTER(LEN=255) :: errMsg             ! Error message
+    CHARACTER(LEN=255) :: caller             ! Name of this routine
+
+    ! Saved scalars
+    INTEGER, SAVE      :: lastDate = -1      ! Stores last YYYYMMDD value
+    INTEGER, SAVE      :: lastTime = -1      ! Stores last hhmmss value
+
+    ! Arrays
+    REAL*4             :: Q(State_Grid%NX,State_Grid%NY,State_Grid%NZ) ! Temporary data arrray
+
+    !======================================================================
+    ! Skip if we have already read data for this date & time
+    !======================================================================
+    IF ( YYYYMMDD == lastDate .and. HHMMSS == lastTime ) THEN
+       stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
+       WRITE( 6, 20 ) stamp
+ 20    FORMAT( '     - FLEXGRID A1dyn met fields for ', a,  &
+               ' have been read already'                  )
+       RETURN
+    ENDIF
+
+    !======================================================================
+    ! Select the proper time slice
+    !======================================================================
+
+    ! Name of this routine (for error printout)
+    caller  = "FlexGrid_Read_A1dyn (flexgrid_read_mod.F90)"
+
+    ! Find the proper time-slice to read from disk
+    t_index = ( HHMMSS / 10000 ) + 1
+
+    ! Stop w/ error if the time index is invalid
+    IF ( t_index < 1 .or. t_index > 24 ) THEN
+       WRITE( errMsg, 100 ) t_index
+ 100   FORMAT( 'Time_index value ', i5, ' must be in the range 1 to 24!' )
+       CALL Error_Stop( errMsg, caller )
+    ENDIF
+
+    !======================================================================
+    ! Get met fields from HEMCO
+    !======================================================================
+
+    ! Read U
+    v_name = "U"
+    CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
+    State_Met%U = Q
+
+    ! Read V
+    v_name = "V"
+    CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
+    State_Met%V = Q
+
+    ! Echo info
+    stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
+    WRITE( 6, 10 ) stamp
+ 10 FORMAT( '     - Found all A1dyn  met fields for ', a )
+
+
+    ! Save date & time for next iteration
+    lastDate = YYYYMMDD
+    lastTime = HHMMSS
+
+  END SUBROUTINE FlexGrid_Read_A1dyn
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
 ! !IROUTINE: FlexGrid_Read_a3
 !
 ! !DESCRIPTION: Convenience wrapper for the following routines which read
@@ -860,15 +1001,20 @@ SUBROUTINE FlexGrid_Read_A3dyn( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
     CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
     State_Met%RH = Q
 
-    ! Read U
-    v_name = "U"
-    CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
-    State_Met%U = Q
+    ! 0.125x0.15625 uses A1dyn archive
+    IF ( TRIM(State_Grid%GridRes) /= '0.125x0.15625' ) THEN
 
-    ! Read V
-    v_name = "V"
-    CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
-    State_Met%V = Q
+        ! Read U
+        v_name = "U"
+        CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
+        State_Met%U = Q
+
+        ! Read V
+        v_name = "V"
+        CALL Get_Met_3D( Input_Opt, State_Grid, Q, TRIM(v_name), t_index=t_index )
+        State_Met%V = Q
+
+    ENDIF
 
     ! Echo info
     stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
@@ -1226,6 +1372,170 @@ SUBROUTINE FlexGrid_Read_I3_1( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
     ! Get met fields from HEMCO
     !======================================================================
 
+    ! Name of this routine (for error printout)
+    caller = 'FlexGrid_Read_I3_1 (flexgrid_read_mod.F90)'
+
+    ! Find the proper time-slice to read from disk
+    t_index = ( HHMMSS / 030000 ) + 1
+
+    ! Stop w/ error if the time index is invalid
+    IF ( t_index < 1 .or. t_index > 8 ) THEN
+       WRITE( errMsg, 100 ) t_index
+ 100   FORMAT( 'Time_index value ', i5, ' must be in the range 1 to 8!' )
+       CALL Error_Stop( errMsg, caller )
+    ENDIF
+
+    ! Resolution 0.125x0.15625 uses I1dyn archive for PS, SPHU (xlwang, 06/2024)
+    IF ( TRIM(State_Grid%GridRes) .NE. '0.125x0.15625' ) THEN
+
+       !-------------------------------------------------
+       ! Read 2D data
+       !-------------------------------------------------
+
+       ! Read PS
+       v_name = "PS"
+       CALL Get_Met_2D( Input_Opt, State_Grid, Q2, TRIM(v_name), t_index=t_index )
+       State_Met%PS1_WET = Q2
+
+       !-------------------------------------------------
+       ! Read 3D data
+       !-------------------------------------------------
+
+       !----------------------------------------------------------------
+       ! Prior to 2/3/12:
+       ! For now, skip reading Potential Vorticity (bmy, 2/3/12)
+       !! Read PV
+       !v_name = "PV"
+       !CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
+       !!Q3 = ABS(1.0e6*Q3) ! PV to PVU
+       !State_Met%PV = Q3
+       !----------------------------------------------------------------
+
+       ! Read SPHU
+       v_name = "SPHU"
+       CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
+       State_Met%SPHU1 = Q3
+
+    ENDIF
+
+    ! Read T
+    v_name = "TMPU"
+    CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
+    State_Met%TMPU1 = Q3
+
+    ! Echo info
+    stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
+    WRITE( 6, 10 ) stamp
+ 10 FORMAT( '     - Found all I3     met fields for ', a )
+
+    !-------------------------------------------------
+    ! Unit conversions & special handling
+    !-------------------------------------------------
+
+    ! Resolution 0.125x0.15625 uses I1dyn archive for PS, SPHU (xlwang, 06/2024)
+    IF ( TRIM(State_Grid%GridRes) /= '0.125x0.15625' ) THEN
+
+        WHERE ( State_Met%SPHU1 < 0d0 )
+
+           ! NOTE: Now set negative Q to a small positive #
+           ! instead of zero, so as not to blow up logarithms
+           State_Met%SPHU1 = 1d-32
+
+        ELSEWHERE
+
+           ! Convert GEOS-FP specific humidity from [kg/kg] to [g/kg]
+           State_Met%SPHU1 = State_Met%SPHU1 * 1000d0
+
+        ENDWHERE
+
+        IF ( TRIM(Input_Opt%MetField) == 'MERRA2'    .or. &
+             TRIM(Input_Opt%MetField) == 'MODELE2.1' .or. & 
+             TRIM(Input_Opt%MetField) == 'MODELE2.2' ) THEN
+           ! Convert PS1_WET from [Pa] to [hPa]
+           State_Met%PS1_WET = State_Met%PS1_WET * 1e-2_fp
+        ENDIF
+
+        ! Initialize State_Met%SPHU to State_Met%SPHU1.  After all future MET
+        ! field reads (flexgrid_read_i3_2) we will interpolate State_Met%SPHU
+        ! from the values of State_Met vars SPHU1 and SPHU2.
+        State_Met%SPHU = State_Met%SPHU1
+
+    ENDIF
+
+    ! Initialize State_Met%T to State_Met%TMPU1.  After all future MET
+    ! field reads (flexgrid_read_i3_2) we will interpolate State_Met%T
+    ! from the values of State_Met vars TMPU1 and TMPU2.
+    State_Met%T = State_Met%TMPU1
+
+  END SUBROUTINE FlexGrid_Read_I3_1
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
+! !IROUTINE: FlexGrid_Read_I3_2
+!
+! !DESCRIPTION: Routine to read variables and attributes from a NetCDF
+!  met fields file containing 3-hr instantaneous (I3) data.
+!\\
+!\\
+! !INTERFACE:
+!
+  SUBROUTINE FlexGrid_Read_I3_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
+                                 State_Met )
+!
+! !USES:
+!
+    USE Input_Opt_Mod,      ONLY : OptInput
+    USE State_Grid_Mod,     ONLY : GrdState
+    USE State_Met_Mod,      ONLY : MetState
+    USE Get_Met_Mod
+!
+! !INPUT PARAMETERS:
+!
+    INTEGER,        INTENT(IN)    :: YYYYMMDD   ! GMT date in YYYY/MM/DD format
+    INTEGER,        INTENT(IN)    :: HHMMSS     ! GMT time in hh:mm:ss   format
+    TYPE(OptInput), INTENT(IN)    :: Input_Opt  ! Input Options object
+    TYPE(GrdState), INTENT(IN)    :: State_Grid ! Grid State object
+!
+! !INPUT/OUTPUT PARAMETERS:
+!
+    TYPE(MetState), INTENT(INOUT) :: State_Met  ! Meteorology State object
+!
+! !REMARKS:
+!  This routine was automatically generated by the Perl script ncCodeRead,
+!  and was subsequently hand-edited for compatibility with GEOS-Chem.
+!                                                                             .
+!  Even though the netCDF file is self-describing, the GEOS-FP data,
+!  dimensions, and units are pre-specified according to the GMAO GEOS-FP
+!  file specification.  Therefore we can "cheat" a little bit and not have
+!  to read netCDF attributes to find what these values are.
+!
+! !REVISION HISTORY:
+!  30 Jan 2012 - R. Yantosca - Initial version
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+! !LOCAL VARIABLES:
+!
+    ! Scalars
+    INTEGER            :: t_index                  ! Time index
+    CHARACTER(LEN=16)  :: stamp                    ! Time and date stamp
+    CHARACTER(LEN=255) :: v_name                   ! netCDF variable name
+    CHARACTER(LEN=255) :: errMsg                   ! Error message
+    CHARACTER(LEN=255) :: caller                   ! Name of this routine
+
+    ! Arrays
+    REAL*4             :: Q2(State_Grid%NX,State_Grid%NY      )         ! 2D temporary data arrray
+    REAL*4             :: Q3(State_Grid%NX,State_Grid%NY,State_Grid%NZ) ! 3D temporary data arrray
+
+    !======================================================================
+    ! Get met fields from HEMCO
+    !======================================================================
+
     ! Name of this routine (for error printout)
     caller = 'FlexGrid_Read_I3_2 (flexgrid_read_mod.F90)'
 
@@ -1239,6 +1549,224 @@ SUBROUTINE FlexGrid_Read_I3_1( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
        CALL Error_Stop( errMsg, caller )
     ENDIF
 
+    ! Resolution 0.125x0.15625 uses I1dyn archive  for PS, SPHU (xlwang, 06/2024)
+    IF ( TRIM(State_Grid%GridRes) .NE. '0.125x0.15625' ) THEN
+
+       !-------------------------------------------------
+       ! Read 2D data
+       !-------------------------------------------------
+
+       ! Read PS
+       IF ( HHMMSS == 000000 ) THEN
+          v_name = "PS_NEXTDAY"
+       ELSE
+          v_name = "PS"
+       ENDIF
+       CALL Get_Met_2D( Input_Opt, State_Grid, Q2, TRIM(v_name), t_index=t_index )
+       State_Met%PS2_WET = Q2
+
+       !-------------------------------------------------
+       ! Read 3D data
+       !-------------------------------------------------
+
+       !----------------------------------------------------------------
+       ! Prior to 2/3/12:
+       ! For now, skip reading Potential Vorticity (bmy, 2/3/12)
+       !! Read PV
+       !IF ( HHMMSS == 000000 ) THEN
+       !   v_name = "PV_NEXTDAY"
+       !ELSE
+       !   v_name = "PV"
+       !ENDIF
+       !CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
+       !!Q3 = ABS(1.0e6*Q3) ! PV to PVU
+       !State_Met%PV = Q3
+       !----------------------------------------------------------------
+
+       ! Read SPHU
+       IF ( HHMMSS == 000000 ) THEN
+          v_name = "SPHU_NEXTDAY"
+       ELSE
+          v_name = "SPHU"
+       ENDIF
+       CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
+       State_Met%SPHU2 = Q3
+
+    ENDIF
+
+    !-------------------------------------------------
+    ! Read 3D data
+    !-------------------------------------------------
+
+    ! Read T
+    IF ( HHMMSS == 000000 ) THEN
+       v_name = "TMPU_NEXTDAY"
+    ELSE
+       v_name = "TMPU"
+    ENDIF
+    CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
+    State_Met%TMPU2 = Q3
+
+    ! Echo info
+    stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
+    WRITE( 6, 10 ) stamp
+ 10 FORMAT( '     - Found all I3     met fields for ', a )
+
+    !-------------------------------------------------
+    ! Unit conversions & special handling
+    !-------------------------------------------------
+    ! Resolution 0.125x0.15625 uses I1dyn archive for PS, SPHU (xlwang, 06/2024)
+    IF ( TRIM(State_Grid%GridRes) /= '0.125x0.15625' ) THEN
+
+        WHERE ( State_Met%SPHU2 < 0d0 )
+
+           ! NOTE: Now set negative Q to a small positive #
+           ! instead of zero, so as not to blow up logarithms
+           State_Met%SPHU2 = 1d-32
+
+        ELSEWHERE
+
+           ! Convert specific humidity from [kg/kg] to [g/kg]
+           State_Met%SPHU2 = State_Met%SPHU2 * 1000d0
+
+        ENDWHERE
+
+        IF ( TRIM(Input_Opt%MetField) == 'MERRA2'    .or. &
+             TRIM(Input_Opt%MetField) == 'MODELE2.1' .or. & 
+             TRIM(Input_Opt%MetField) == 'MODELE2.2' ) THEN
+           ! Convert PS2_WET from [Pa] to [hPa]
+           State_Met%PS2_WET = State_Met%PS2_WET * 1e-2_fp
+        ENDIF
+
+    ENDIF
+
+  END SUBROUTINE FlexGrid_Read_I3_2
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
+! !IROUTINE: copy_i3_fields
+!
+! !DESCRIPTION: Subroutine COPY\_I3\_FIELDS copies the I-3 fields at the
+!  end of a 3-hr timestep.  The I-3 fields at the end of a given 3-hr timestep
+!  become the fields at the beginning of the next 3-hr timestep.
+!\\
+!\\
+! !INTERFACE:
+!
+      SUBROUTINE COPY_I3_FIELDS( State_Met, State_Grid )
+!
+! !USES:
+!
+      USE State_Met_Mod,        ONLY : MetState
+      USE State_Grid_Mod,       ONLY : GrdState
+!
+! !INPUT PARAMETERS:
+!
+      TYPE(GrdState), INTENT(IN)    :: State_Grid ! Grid State object
+      TYPE(MetState), INTENT(INOUT) :: State_Met   ! Meteorology State object
+!
+! !REVISION HISTORY:
+!  13 Apr 2004 - R. Yantosca - Initial version
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+    ! Resolution 0.125x0.15625 uses I1dyn archive for PS, SPHU (xlwang, 06/2024)
+    IF ( TRIM(State_Grid%GridRes) .NE. '0.125x0.15625' ) THEN
+      State_Met%PS1_WET = State_Met%PS2_WET ! I3 surface pressure    [hPa]
+      State_Met%PS1_DRY = State_Met%PS2_DRY ! I3 surface pressure    [hPa]
+      State_Met%SPHU1   = State_Met%SPHU2   ! I3 specific humidity   [g/kg]
+    ENDIF
+
+    State_Met%TMPU1     = State_Met%TMPU2   ! I3 temperature         [K]
+
+
+      END SUBROUTINE COPY_I3_FIELDS
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
+! !IROUTINE: FlexGrid_Read_I1dyn_1
+!
+! !DESCRIPTION: Routine to read variables and attributes from a NetCDF
+!  met fields file containing 1-hr instantaneous (I1dyn) data.
+!\\
+!\\
+! !INTERFACE:
+!
+  SUBROUTINE FlexGrid_Read_I1dyn_1( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
+                                    State_Met )
+!
+! !USES:
+!
+    USE Input_Opt_Mod,      ONLY : OptInput
+    USE State_Grid_Mod,     ONLY : GrdState
+    USE State_Met_Mod,      ONLY : MetState
+    USE Get_Met_Mod
+!
+! !INPUT PARAMETERS:
+!
+    INTEGER,        INTENT(IN)    :: YYYYMMDD   ! GMT date in YYYY/MM/DD format
+    INTEGER,        INTENT(IN)    :: HHMMSS     ! GMT time in hh:mm:ss   format
+    TYPE(OptInput), INTENT(IN)    :: Input_Opt  ! Input Options object
+    TYPE(GrdState), INTENT(IN)    :: State_Grid ! Grid State object
+!
+! !INPUT/OUTPUT PARAMETERS:
+!
+    TYPE(MetState), INTENT(INOUT) :: State_Met  ! Meteorology State object
+!
+! !REMARKS:
+!  This routine was automatically generated by the Perl script ncCodeRead,
+!  and was subsequently hand-edited for compatibility with GEOS-Chem.
+!                                                                             .
+!  Even though the netCDF file is self-describing, the GEOS-FP data,
+!  dimensions, and units are pre-specified according to the GMAO GEOS-FP
+!  file specification.  Therefore we can "cheat" a little bit and not have
+!  to read netCDF attributes to find what these values are.
+!
+! !REVISION HISTORY:
+!  30 Jan 2012 - R. Yantosca - Initial version
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+! !LOCAL VARIABLES:
+!
+    ! Scalars
+    INTEGER            :: t_index            ! Time index
+    CHARACTER(LEN=16)  :: stamp              ! Time and date stamp
+    CHARACTER(LEN=255) :: v_name             ! netCDF variable name
+    CHARACTER(LEN=255) :: errMsg             ! Error message
+    CHARACTER(LEN=255) :: caller             ! Name of this routine
+
+    ! Arrays
+    REAL*4             :: Q2(State_Grid%NX,State_Grid%NY      )         ! 2D temporary data arrray
+    REAL*4             :: Q3(State_Grid%NX,State_Grid%NY,State_Grid%NZ) ! 3D temporary data arrray
+
+    !======================================================================
+    ! Get met fields from HEMCO
+    !======================================================================
+
+    ! Name of this routine (for error printout)
+    caller = 'FlexGrid_Read_I1dyn_1 (flexgrid_read_mod.F90)'
+
+    ! Find the proper time-slice to read from disk
+    t_index = ( HHMMSS / 10000 ) + 1
+
+    ! Stop w/ error if the time index is invalid
+    IF ( t_index < 1 .or. t_index > 24 ) THEN
+       WRITE( errMsg, 100 ) t_index
+ 100   FORMAT( 'Time_index value ', i5, ' must be in the range 1 to 24!' )
+       CALL Error_Stop( errMsg, caller )
+    ENDIF
+
     !-------------------------------------------------
     ! Read 2D data
     !-------------------------------------------------
@@ -1252,30 +1780,15 @@ SUBROUTINE FlexGrid_Read_I3_1( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
     ! Read 3D data
     !-------------------------------------------------
 
-    !----------------------------------------------------------------
-    ! Prior to 2/3/12:
-    ! For now, skip reading Potential Vorticity (bmy, 2/3/12)
-    !! Read PV
-    !v_name = "PV"
-    !CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
-    !!Q3 = ABS(1.0e6*Q3) ! PV to PVU
-    !State_Met%PV = Q3
-    !----------------------------------------------------------------
-
-    ! Read QV
+    ! Read SPHU
     v_name = "SPHU"
     CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
     State_Met%SPHU1 = Q3
 
-    ! Read T
-    v_name = "TMPU"
-    CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
-    State_Met%TMPU1 = Q3
-
     ! Echo info
     stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
     WRITE( 6, 10 ) stamp
- 10 FORMAT( '     - Found all I3     met fields for ', a )
+ 10 FORMAT( '     - Found all I1dyn     met fields for ', a )
 
     !-------------------------------------------------
     ! Unit conversions & special handling
@@ -1300,30 +1813,27 @@ SUBROUTINE FlexGrid_Read_I3_1( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
        State_Met%PS1_WET = State_Met%PS1_WET * 1e-2_fp
     ENDIF
 
-    ! Initialize State_Met%T to State_Met%TMPU1 and State_Met%SPHU to
-    ! State_Met%SPHU1.  After all future MET field reads (flexgrid_read_i3_2)
-    ! we will interpolate State_Met%T from the values of State_Met vars
-    ! TMPU1 and TMPU2 and State_Met%SPHU from the values of State_Met vars
-    ! SPHU1 and SPHU2.
-    State_Met%T         = State_Met%TMPU1
-    State_Met%SPHU      = State_Met%SPHU1
+    ! Initialize State_Met%SPHU to State_Met%SPHU1.  After all future MET
+    ! field reads (flexgrid_read_I1dyn_2) we will interpolate State_Met%SPHU
+    ! from the values of State_Met vars SPHU1 and SPHU2.
+    State_Met%SPHU = State_Met%SPHU1
 
-  END SUBROUTINE FlexGrid_Read_I3_1
+  END SUBROUTINE FlexGrid_Read_I1dyn_1
 !EOC
 !------------------------------------------------------------------------------
 !                  GEOS-Chem Global Chemical Transport Model                  !
 !------------------------------------------------------------------------------
 !BOP
 !
-! !IROUTINE: FlexGrid_Read_I3_2
+! !IROUTINE: FlexGrid_Read_I1dyn_2
 !
 ! !DESCRIPTION: Routine to read variables and attributes from a NetCDF
-!  met fields file containing 3-hr instantaneous (I3) data.
+!  met fields file containing 1-hr instantaneous (I1dyn) data.
 !\\
 !\\
 ! !INTERFACE:
 !
-  SUBROUTINE FlexGrid_Read_I3_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
+  SUBROUTINE FlexGrid_Read_I1dyn_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
                                  State_Met )
 !
 ! !USES:
@@ -1378,15 +1888,15 @@ SUBROUTINE FlexGrid_Read_I3_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
     !======================================================================
 
     ! Name of this routine (for error printout)
-    caller = 'FlexGrid_Read_I3_2 (flexgrid_read_mod.F90)'
+    caller = 'FlexGrid_Read_I1dyn_2 (flexgrid_read_mod.F90)'
 
     ! Find the proper time-slice to read from disk
-    t_index = ( HHMMSS / 030000 ) + 1
+    t_index = ( HHMMSS / 10000 ) + 1
 
     ! Stop w/ error if the time index is invalid
-    IF ( t_index < 1 .or. t_index > 8 ) THEN
+    IF ( t_index < 1 .or. t_index > 24 ) THEN
        WRITE( errMsg, 100 ) t_index
- 100   FORMAT( 'Time_index value ', i5, ' must be in the range 1 to 8!' )
+ 100   FORMAT( 'Time_index value ', i5, ' must be in the range 1 to 24!' )
        CALL Error_Stop( errMsg, caller )
     ENDIF
 
@@ -1407,21 +1917,7 @@ SUBROUTINE FlexGrid_Read_I3_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
     ! Read 3D data
     !-------------------------------------------------
 
-    !----------------------------------------------------------------
-    ! Prior to 2/3/12:
-    ! For now, skip reading Potential Vorticity (bmy, 2/3/12)
-    !! Read PV
-    !IF ( HHMMSS == 000000 ) THEN
-    !   v_name = "PV_NEXTDAY"
-    !ELSE
-    !   v_name = "PV"
-    !ENDIF
-    !CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
-    !!Q3 = ABS(1.0e6*Q3) ! PV to PVU
-    !State_Met%PV = Q3
-    !----------------------------------------------------------------
-
-    ! Read QV
+    ! Read SPHU
     IF ( HHMMSS == 000000 ) THEN
        v_name = "SPHU_NEXTDAY"
     ELSE
@@ -1430,19 +1926,10 @@ SUBROUTINE FlexGrid_Read_I3_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
     CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
     State_Met%SPHU2 = Q3
 
-    ! Read T
-    IF ( HHMMSS == 000000 ) THEN
-       v_name = "TMPU_NEXTDAY"
-    ELSE
-       v_name = "TMPU"
-    ENDIF
-    CALL Get_Met_3D( Input_Opt, State_Grid, Q3, TRIM(v_name), t_index=t_index )
-    State_Met%TMPU2 = Q3
-
     ! Echo info
     stamp = TimeStamp_String( YYYYMMDD, HHMMSS )
     WRITE( 6, 10 ) stamp
- 10 FORMAT( '     - Found all I3     met fields for ', a )
+ 10 FORMAT( '     - Found all I1dyn     met fields for ', a )
 
     !-------------------------------------------------
     ! Unit conversions & special handling
@@ -1467,23 +1954,23 @@ SUBROUTINE FlexGrid_Read_I3_2( YYYYMMDD, HHMMSS, Input_Opt, State_Grid, &
        State_Met%PS2_WET = State_Met%PS2_WET * 1e-2_fp
     ENDIF
 
-  END SUBROUTINE FlexGrid_Read_I3_2
+  END SUBROUTINE FlexGrid_Read_I1dyn_2
 !EOC
 !------------------------------------------------------------------------------
 !                  GEOS-Chem Global Chemical Transport Model                  !
 !------------------------------------------------------------------------------
 !BOP
 !
-! !IROUTINE: copy_i3_fields
+! !IROUTINE: copy_I1dyn_fields
 !
-! !DESCRIPTION: Subroutine COPY\_I3\_FIELDS copies the I-3 fields at the
-!  end of a 3-hr timestep.  The I-3 fields at the end of a given 3-hr timestep
-!  become the fields at the beginning of the next 3-hr timestep.
+! !DESCRIPTION: Subroutine COPY\_I1dyn\_FIELDS copies the I-1 fields at the
+!  end of a 1-hr timestep.  The I-1 fields at the end of a given 1-hr timestep
+!  become the fields at the beginning of the next 1-hr timestep.
 !\\
 !\\
 ! !INTERFACE:
 !
-      SUBROUTINE COPY_I3_FIELDS( State_Met )
+      SUBROUTINE COPY_I1dyn_FIELDS( State_Met )
 !
 ! !USES:
 !
@@ -1500,12 +1987,11 @@ SUBROUTINE COPY_I3_FIELDS( State_Met )
 !------------------------------------------------------------------------------
 !BOC
 !
-      State_Met%PS1_WET = State_Met%PS2_WET ! I3 surface pressure    [hPa]
-      State_Met%PS1_DRY = State_Met%PS2_DRY ! I3 surface pressure    [hPa]
-      State_Met%SPHU1   = State_Met%SPHU2   ! I3 specific humidity   [g/kg]
-      State_Met%TMPU1   = State_Met%TMPU2   ! I3 temperature         [K]
+      State_Met%PS1_WET = State_Met%PS2_WET ! I1dyn surface pressure    [hPa]
+      State_Met%PS1_DRY = State_Met%PS2_DRY ! I1dyn surface pressure    [hPa]
+      State_Met%SPHU1   = State_Met%SPHU2   ! I1dyn specific humidity   [g/kg]
 
-      END SUBROUTINE COPY_I3_FIELDS
+      END SUBROUTINE COPY_I1dyn_FIELDS
 !EOC
 END MODULE FlexGrid_Read_Mod
 #endif
diff --git a/GeosCore/hco_interface_gc_mod.F90 b/GeosCore/hco_interface_gc_mod.F90
index 3391b9bf8..61f94da0c 100644
--- a/GeosCore/hco_interface_gc_mod.F90
+++ b/GeosCore/hco_interface_gc_mod.F90
@@ -4363,6 +4363,10 @@ SUBROUTINE Get_Met_Fields( Input_Opt, State_Chm, State_Grid, &
    IF ( PHASE == 0 .or. ITS_TIME_FOR_A1() .and. &
         .not. ITS_TIME_FOR_EXIT() ) THEN
       CALL FlexGrid_Read_A1( D(1), D(2), Input_Opt, State_Grid, State_Met )
+
+      IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+         CALL FlexGrid_Read_A1dyn( D(1), D(2), Input_Opt, State_Grid, State_Met )
+      ENDIF
    ENDIF
 
    !----------------------------------
@@ -4385,41 +4389,46 @@ SUBROUTINE Get_Met_Fields( Input_Opt, State_Chm, State_Grid, &
       D = GET_FIRST_I3_TIME()
       CALL FlexGrid_Read_I3_1( D(1), D(2), Input_Opt, State_Grid, State_Met )
 
-      ! Get delta pressure per grid box stored in restart file to allow
-      ! mass conservation across consecutive runs.
-      v_name = 'DELPDRY'
-      CALL HCO_GC_GetPtr( Input_Opt, State_Grid, TRIM(v_name), Ptr3D, RC, FOUND=FOUND )
-      IF ( FOUND ) THEN
-         State_Met%DELP_DRY = Ptr3D
-         IF ( Input_Opt%amIRoot ) THEN
-            WRITE(6,*) 'Initialize DELP_DRY from restart file'
-         ENDIF
-      ELSE
-         IF ( Input_Opt%amIRoot ) THEN
-            WRITE(6,*) 'DELP_DRY not found in restart, set to zero'
-         ENDIF
-      ENDIF
-      Ptr3D => NULL()
+      ! Resolution 0.125x0.15625 uses I1dyn archive (xlwang, 06/2024)
+      IF ( TRIM(State_Grid%GridRes) /= '0.125x0.15625' ) THEN
+
+          ! Get delta pressure per grid box stored in restart file to allow
+          ! mass conservation across consecutive runs.
+          v_name = 'DELPDRY'
+          CALL HCO_GC_GetPtr( Input_Opt, State_Grid, TRIM(v_name), Ptr3D, RC, FOUND=FOUND )
+          IF ( FOUND ) THEN
+             State_Met%DELP_DRY = Ptr3D
+             IF ( Input_Opt%amIRoot ) THEN
+                WRITE(6,*) 'Initialize DELP_DRY from restart file'
+             ENDIF
+          ELSE
+             IF ( Input_Opt%amIRoot ) THEN
+                WRITE(6,*) 'DELP_DRY not found in restart, set to zero'
+             ENDIF
+          ENDIF
+          Ptr3D => NULL()
+
+          ! Set dry surface pressure (PS1_DRY) from State_Met%PS1_WET
+          ! and compute avg dry pressure near polar caps
+          CALL Set_Dry_Surface_Pressure( State_Grid, State_Met, 1 )
+          CALL AvgPole( State_Grid, State_Met%PS1_DRY )
 
-      ! Set dry surface pressure (PS1_DRY) from State_Met%PS1_WET
-      ! and compute avg dry pressure near polar caps
-      CALL Set_Dry_Surface_Pressure( State_Grid, State_Met, 1 )
-      CALL AvgPole( State_Grid, State_Met%PS1_DRY )
+          ! Compute avg moist pressure near polar caps
+          CALL AvgPole( State_Grid, State_Met%PS1_WET )
 
-      ! Compute avg moist pressure near polar caps
-      CALL AvgPole( State_Grid, State_Met%PS1_WET )
+          ! Initialize surface pressures prior to interpolation
+          ! to allow initialization of floating pressures
+          State_Met%PSC2_WET = State_Met%PS1_WET
+          State_Met%PSC2_DRY = State_Met%PS1_DRY
+          CALL Set_Floating_Pressures( State_Grid, State_Met, RC )
 
-      ! Initialize surface pressures prior to interpolation
-      ! to allow initialization of floating pressures
-      State_Met%PSC2_WET = State_Met%PS1_WET
-      State_Met%PSC2_DRY = State_Met%PS1_DRY
-      CALL Set_Floating_Pressures( State_Grid, State_Met, RC )
+          ! Call AIRQNT to compute initial air mass quantities
+          ! Do not update initial tracer concentrations since not read
+          ! from restart file yet (ewl, 10/28/15)
+          CALL AirQnt( Input_Opt, State_Chm, State_Grid, State_Met, &
+                       RC, update_mixing_ratio=.FALSE. )
 
-      ! Call AIRQNT to compute initial air mass quantities
-      ! Do not update initial tracer concentrations since not read
-      ! from restart file yet (ewl, 10/28/15)
-      CALL AirQnt( Input_Opt, State_Chm, State_Grid, State_Met, &
-                   RC, update_mixing_ratio=.FALSE. )
+      ENDIF ! not 0.125x0.15625
 
    ENDIF
 
@@ -4429,16 +4438,87 @@ SUBROUTINE Get_Met_Fields( Input_Opt, State_Chm, State_Grid, &
       D = GET_I3_TIME()
       CALL FlexGrid_Read_I3_2( D(1), D(2), Input_Opt, State_Grid, State_Met )
 
-      ! Set dry surface pressure (PS2_DRY) from State_Met%PS2_WET
-      ! and compute avg dry pressure near polar caps
-      CALL Set_Dry_Surface_Pressure( State_Grid, State_Met, 2 )
-      CALL AvgPole( State_Grid, State_Met%PS2_DRY )
+      ! Resolution 0.125x0.15625 use I1dyn archive (xlwang, 06/2024)
+      IF ( TRIM(State_Grid%GridRes) .NE. '0.125x0.15625' ) THEN
 
-      ! Compute avg moist pressure near polar caps
-      CALL AvgPole( State_Grid, State_Met%PS2_WET )
+          ! Set dry surface pressure (PS2_DRY) from State_Met%PS2_WET
+          ! and compute avg dry pressure near polar caps
+          CALL Set_Dry_Surface_Pressure( State_Grid, State_Met, 2 )
+          CALL AvgPole( State_Grid, State_Met%PS2_DRY )
+
+          ! Compute avg moist pressure near polar caps
+          CALL AvgPole( State_Grid, State_Met%PS2_WET )
+
+      ENDIF ! not 0.125x0.15625
 
    ENDIF
 
+   !----------------------------------
+   ! Read 1-hr instantanous data
+   !----------------------------------
+
+   ! Resolution 0.125x0.15625 uses I1dyn archive (xlwang, 06/2024)
+   IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+
+       IF ( PHASE == 0 ) THEN
+          D = GET_FIRST_I1dyn_TIME()
+          CALL FlexGrid_Read_I1dyn_1( D(1), D(2), Input_Opt, State_Grid, State_Met )
+
+          ! Get delta pressure per grid box stored in restart file to allow
+          ! mass conservation across consecutive runs.
+          v_name = 'DELPDRY'
+          CALL HCO_GC_GetPtr( Input_Opt, State_Grid, TRIM(v_name), Ptr3D, RC, FOUND=FOUND )
+          IF ( FOUND ) THEN
+             State_Met%DELP_DRY = Ptr3D
+             IF ( Input_Opt%amIRoot ) THEN
+                WRITE(6,*) 'Initialize DELP_DRY from restart file'
+             ENDIF
+          ELSE
+             IF ( Input_Opt%amIRoot ) THEN
+                WRITE(6,*) 'DELP_DRY not found in restart, set to zero'
+             ENDIF
+          ENDIF
+          Ptr3D => NULL()
+
+          ! Set dry surface pressure (PS1_DRY) from State_Met%PS1_WET
+          ! and compute avg dry pressure near polar caps
+          CALL Set_Dry_Surface_Pressure( State_Grid, State_Met, 1 )
+          CALL AvgPole( State_Grid, State_Met%PS1_DRY )
+
+          ! Compute avg moist pressure near polar caps
+          CALL AvgPole( State_Grid, State_Met%PS1_WET )
+
+          ! Initialize surface pressures prior to interpolation
+          ! to allow initialization of floating pressures
+          State_Met%PSC2_WET = State_Met%PS1_WET
+          State_Met%PSC2_DRY = State_Met%PS1_DRY
+          CALL Set_Floating_Pressures( State_Grid, State_Met, RC )
+
+          ! Call AIRQNT to compute initial air mass quantities
+          ! Do not update initial tracer concentrations since not read
+          ! from restart file yet (ewl, 10/28/15)
+          CALL AirQnt( Input_Opt, State_Chm, State_Grid, State_Met, &
+                       RC, update_mixing_ratio=.FALSE. )
+
+       ENDIF
+
+       ! Read in I1dyn fields at t+3hours for this timestep
+       IF ( ITS_TIME_FOR_I1dyn() .and. .not. ITS_TIME_FOR_EXIT() ) THEN
+
+          D = GET_I1dyn_TIME()
+          CALL FlexGrid_Read_I1dyn_2( D(1), D(2), Input_Opt, State_Grid, State_Met )
+
+          ! Set dry surface pressure (PS2_DRY) from State_Met%PS2_WET
+          ! and compute avg dry pressure near polar caps
+          CALL Set_Dry_Surface_Pressure( State_Grid, State_Met, 2 )
+          CALL AvgPole( State_Grid, State_Met%PS2_DRY )
+
+          ! Compute avg moist pressure near polar caps
+          CALL AvgPole( State_Grid, State_Met%PS2_WET )
+
+       ENDIF
+
+    ENDIF
  END SUBROUTINE Get_Met_Fields
 !EOC
 #endif
diff --git a/GeosCore/input_mod.F90 b/GeosCore/input_mod.F90
index 0f85d4a0e..2589d8831 100644
--- a/GeosCore/input_mod.F90
+++ b/GeosCore/input_mod.F90
@@ -957,8 +957,8 @@ SUBROUTINE Config_Grid( Config, Input_Opt, State_Grid, RC )
     ENDIF
 
     ! Save the delta X and Y values
-    State_Grid%DY = Cast_and_RoundOff( subStrs(1), places=4 )
-    State_Grid%DX = Cast_and_RoundOff( subStrs(2), places=4 )
+    State_Grid%DY = Cast_and_RoundOff( subStrs(1), places=6 )
+    State_Grid%DX = Cast_and_RoundOff( subStrs(2), places=6 )
 
     !------------------------------------------------------------------------
     ! Level range
@@ -984,8 +984,8 @@ SUBROUTINE Config_Grid( Config, Input_Opt, State_Grid, RC )
        CALL GC_Error( errMsg, RC, thisLoc )
        RETURN
     ENDIF
-    State_Grid%XMin = Cast_and_RoundOff( a_str(1), places=4 )
-    State_Grid%XMax = Cast_and_RoundOff( a_str(2), places=4 )
+    State_Grid%XMin = Cast_and_RoundOff( a_str(1), places=6 )
+    State_Grid%XMax = Cast_and_RoundOff( a_str(2), places=6 )
 
     ! Make sure values are in valid rangre
     IF ( State_Grid%XMin >= State_Grid%XMax ) THEN
@@ -1021,8 +1021,8 @@ SUBROUTINE Config_Grid( Config, Input_Opt, State_Grid, RC )
        CALL GC_Error( errMsg, RC, thisLoc )
        RETURN
     ENDIF
-    State_Grid%YMin = Cast_and_RoundOff( a_str(1), places=4 )
-    State_Grid%YMax = Cast_and_RoundOff( a_str(2), places=4 )
+    State_Grid%YMin = Cast_and_RoundOff( a_str(1), places=6 )
+    State_Grid%YMax = Cast_and_RoundOff( a_str(2), places=6 )
 
     ! Make sure values are in valid range
     IF ( State_Grid%YMin >= State_Grid%YMax ) THEN
@@ -4659,6 +4659,8 @@ SUBROUTINE Check_Time_Steps( Input_Opt, State_Grid, RC )
        MAX_DYN = 600
     ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
        MAX_DYN = 300
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+       MAX_DYN = 300
     ELSE
        MAX_DYN = 3600
     ENDIF
diff --git a/GeosCore/pjc_pfix_window_mod.F90 b/GeosCore/pjc_pfix_window_mod.F90
index 6d7fd1e6e..cdc7716cf 100644
--- a/GeosCore/pjc_pfix_window_mod.F90
+++ b/GeosCore/pjc_pfix_window_mod.F90
@@ -1209,12 +1209,15 @@ SUBROUTINE Convert_Winds(State_Grid, igd, tdt, cosp, crx, cry, uu, vv)
        ri2   = i2_gl
        rj2m1 = j2_gl - 1
 
-       IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
-          dl    = 2.0e+0_fp * PI / 1152.0_fp
-          dp    = PI /720e+0_fp
-       ELSEIF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+       IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
           dl    = 2.0e+0_fp * PI / 576.0_fp
           dp    = PI /360e+0_fp
+       ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
+          dl    = 2.0e+0_fp * PI / 1152.0_fp
+          dp    = PI /720e+0_fp
+       ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+          dl    = 2.0e+0_fp * PI / 2304.0_fp
+          dp    = PI /1440e+0_fp
        ENDIF
 
        dtdy  = tdt / (Re * dp)
@@ -1373,12 +1376,15 @@ SUBROUTINE Calc_Horiz_Mass_Flux &
     ri2   = i2_gl
     rj2m1 = j2_gl - 1
 
-    IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
-       dl    = 2.0e+0_fp * PI / 1152.0_fp
-       dp    = PI /720.0_fp
-    ELSEIF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+    IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
        dl    = 2.0e+0_fp * PI / 576.0_fp
        dp    = PI /360.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
+       dl    = 2.0e+0_fp * PI / 1152.0_fp
+       dp    = PI /720.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+       dl    = 2.0e+0_fp * PI / 2304.0_fp
+       dp    = PI /1440.0_fp
     ENDIF
 
     facty  = 0.5_fp * tdt / (Re * dp)
@@ -1866,18 +1872,22 @@ SUBROUTINE INIT_PJC_PFIX_WINDOW( State_Grid )
     ENDDO
 
     ! Longitude spacing
-    IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
-       DLON_FV    = 2.0_fp * PI / 1152.0_fp
-    ELSE IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+    IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
        DLON_FV    = 2.0_fp * PI / 576.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
+       DLON_FV    = 2.0_fp * PI / 1152.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+       DLON_FV    = 2.0_fp * PI / 2304.0_fp
     ENDIF
     
     ! Latitude edge at south pole [radians]
     !ELAT_FV(1) = -0.5e+0_fp * PI
-    IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
-       ELAT_FV(1) = CLAT_FV(1) - 0.125_fp * PI / 180.0_fp
-    ELSE IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+    IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
        ELAT_FV(1) = CLAT_FV(1) - 0.25_fp  * PI / 180.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
+       ELAT_FV(1) = CLAT_FV(1) - 0.125_fp * PI / 180.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+       ELAT_FV(1) = CLAT_FV(1) - 0.0625_fp * PI / 180.0_fp
     ENDIF
 
     ! SIN and COS of lat edge at south pole [unitless]
@@ -1897,10 +1907,12 @@ SUBROUTINE INIT_PJC_PFIX_WINDOW( State_Grid )
     ! Latitude edge at North Pole [radians]
     !ELAT_FV(J2_GL+1) = 0.5e+0_fp * PI
     ! for nested NA or EA (lzh, 07/20/2010)
-    IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
-       ELAT_FV(J2_GL+1) = CLAT_FV(J2_GL)+0.125_fp * PI / 180.0_fp
-    ELSE IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+    IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
        ELAT_FV(J2_GL+1) = CLAT_FV(J2_GL)+0.25_fp  * PI / 180.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
+       ELAT_FV(J2_GL+1) = CLAT_FV(J2_GL)+0.125_fp * PI / 180.0_fp
+    ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+       ELAT_FV(J2_GL+1) = CLAT_FV(J2_GL)+0.0625_fp * PI / 180.0_fp
     ENDIF
 
     ! SIN of lat edge at North Pole
diff --git a/GeosCore/sulfate_mod.F90 b/GeosCore/sulfate_mod.F90
index dbc815db9..b2c578e4f 100644
--- a/GeosCore/sulfate_mod.F90
+++ b/GeosCore/sulfate_mod.F90
@@ -1122,16 +1122,18 @@ SUBROUTINE SRCSF30( Input_Opt, State_Grid, State_Met, State_Chm, TC2, RC )
     !AREA3D(:,:,1) = AREA(:,:)
     !AREA3D(:,:,2) = AREA(:,:)
     
-     ! comment out if shut off subgridcoag bc,14/12/23
+    ! comment out if shut off subgridcoag bc,14/12/23
     ! Define subgrid coagulation timescale (win, 10/28/08)
     !IF ( TRIM(State_Grid%GridRes) == '4.0x5.0' ) THEN
     !   TSCALE = 10.0_fp*3600.0_fp  ! 10 hours
     !ELSE IF ( TRIM(State_Grid%GridRes) == '2.0x2.5' ) THEN
        TSCALE = 5.0_fp*3600.0_fp
-    !!ELSE IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+    !ELSE IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
     !   TSCALE = 1.0_fp*3600.0_fp
     !ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
     !   TSCALE = 0.5_fp*3600.0_fp
+    !ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+    !   TSCALE = 0.25*3600.
     !ENDIF
 
     ! Point to species array
diff --git a/GeosCore/tomas_mod.F90 b/GeosCore/tomas_mod.F90
index 85c1c8d37..badce1353 100644
--- a/GeosCore/tomas_mod.F90
+++ b/GeosCore/tomas_mod.F90
@@ -6483,6 +6483,8 @@ SUBROUTINE INIT_TOMAS( Input_Opt, State_Chm, State_Grid, RC )
     !   SGCTSCALE = 1.0_fp*3600.0_fp
     !ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
     !   SGCTSCALE = 0.50_fp*3600.0_fp
+    !ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+    !   SGCTSCALE = 0.25*3600.
     !ENDIF
 
 #if defined(TOMAS40)
diff --git a/GeosCore/tpcore_window_mod.F90 b/GeosCore/tpcore_window_mod.F90
index 6b05e6c17..6e0705d80 100644
--- a/GeosCore/tpcore_window_mod.F90
+++ b/GeosCore/tpcore_window_mod.F90
@@ -301,10 +301,12 @@ subroutine init_WINDOW(State_Grid, im,jm,km,jfirst,jlast,ng, mg, dt, ae, clat)
 
  pi = 4. * atan(1.)
 
- IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
-    dlon = 2.*pi / float(1152)      !(dan)
- ELSEIF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
-    dlon = 2.*pi / float(576)       !(dan)
+ IF ( TRIM(State_Grid%GridRes) == '0.5x0.625' ) THEN
+    dlon = 2.*pi / float(576)
+ ELSE IF ( TRIM(State_Grid%GridRes) == '0.25x0.3125' ) THEN
+    dlon = 2.*pi / float(1152)
+ ELSE IF ( TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+    dlon = 2.*pi / float(2304)
  ENDIF
 
     ! dan for window
diff --git a/GeosUtil/time_mod.F90 b/GeosUtil/time_mod.F90
index 8e3ca7a0e..e35f3ef46 100644
--- a/GeosUtil/time_mod.F90
+++ b/GeosUtil/time_mod.F90
@@ -62,10 +62,12 @@ MODULE TIME_MOD
   PUBLIC  :: GET_A1_TIME
   PUBLIC  :: GET_A3_TIME
   PUBLIC  :: GET_I3_TIME
+  PUBLIC  :: GET_I1dyn_TIME
   PUBLIC  :: GET_BC_TIME
   PUBLIC  :: GET_FIRST_A1_TIME
   PUBLIC  :: GET_FIRST_A3_TIME
   PUBLIC  :: GET_FIRST_I3_TIME
+  PUBLIC  :: GET_FIRST_I1dyn_TIME
   PUBLIC  :: GET_FIRST_BC_TIME
   PUBLIC  :: ITS_TIME_FOR_CHEM
   PUBLIC  :: ITS_TIME_FOR_CONV
@@ -78,6 +80,7 @@ MODULE TIME_MOD
   PUBLIC  :: ITS_TIME_FOR_A1
   PUBLIC  :: ITS_TIME_FOR_A3
   PUBLIC  :: ITS_TIME_FOR_I3
+  PUBLIC  :: ITS_TIME_FOR_I1dyn
   PUBLIC  :: ITS_TIME_FOR_BC
   PUBLIC  :: ITS_TIME_FOR_EXIT
   PUBLIC  :: ITS_MIDMONTH
@@ -1726,6 +1729,81 @@ END FUNCTION GET_I3_TIME
 !------------------------------------------------------------------------------
 !BOP
 !
+! !IROUTINE: Get_i1dyn_time
+!
+! !DESCRIPTION: Function GET\_I1dyn\_TIME returns the correct YYYYMMDD and
+!  HHMMSS values that are needed to read in the next instantaneous 1-hour
+!  (I-1) fields.
+!\\
+!\\
+! !INTERFACE:
+!
+  FUNCTION GET_I1dyn_TIME() RESULT( DATE )
+!
+! !RETURN VALUE:
+!
+    INTEGER :: DATE(2)   ! YYYYMMDD and HHMMSS values
+!
+! !REMARKS:
+!  Modified for start times other than 0 GMT.
+!
+! !REVISION HISTORY:
+!  15 Jun 2024 - X. Wang - Initial version, for 0.125x0.15625
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+! !LOCAL VARIABLES:
+!
+    LOGICAL, SAVE :: FIRST = .TRUE.
+    INTEGER       :: HH, MM, SS, SECS, OFFSET
+
+    !=================================================================
+    ! ALL MET FIELDS:
+    !=================================================================
+
+    IF ( FIRST ) THEN
+
+       !--------------------------------------------------------------
+       ! FIRST-TIME ONLY!  Get the proper # of hours until the next
+       ! I1dyn time.  Also works for start times other than 0 GMT.
+       !--------------------------------------------------------------
+
+       ! Split NHMS into hours, mins, seconds
+       CALL YMD_EXTRACT( NHMS, HH, MM, SS )
+
+       ! Compute seconds elapsed in the 1-hour interval
+       SECS   = MOD( HH, 1 )*3600 + MM*60 + SS
+
+       ! Compute offset to next I-1 time
+       OFFSET = 3600 - SECS
+
+       ! Get YYYY/MM/DD and hh:mm:ss to next I1dyn time
+       DATE   = GET_TIME_AHEAD( OFFSET )
+
+       ! Reset first-time flag
+       FIRST = .FALSE.
+
+    ELSE
+
+       !--------------------------------------------------------------
+       ! Other than the 1st time: Search 180 mins ahead
+       !--------------------------------------------------------------
+
+       ! We need to read in the I-1 fields 1h (60 mins, or 3600 secs)
+       ! ahead of time
+       DATE = GET_TIME_AHEAD( 3600 )
+
+    ENDIF
+
+  END FUNCTION GET_I1dyn_TIME
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
 ! !IROUTINE: Get_bc_time
 !
 ! !DESCRIPTION: Function GET\_BC\_TIME returns the correct YYYYMMDD and HHMMSS
@@ -1922,6 +2000,54 @@ END FUNCTION GET_FIRST_I3_TIME
 !------------------------------------------------------------------------------
 !BOP
 !
+! !IROUTINE: Get_first_i1dyn_time
+!
+! !DESCRIPTION: Function GET\_FIRST\_I1dyn\_TIME returns the correct YYYYMMDD and
+!  HHMMSS values the first time that I-1 fields are read in from disk.
+!\\
+!\\
+! !INTERFACE:
+!
+  FUNCTION GET_FIRST_I1dyn_TIME() RESULT( DATE )
+!
+! !RETURN VALUE:
+!
+    INTEGER :: DATE(2)    ! YYYYMMDD, HHMMSS values
+!
+! !REVISION HISTORY:
+!  15 Jun 2024 - X. Wang - Initial version, for 0.125x0.15625
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+! !LOCAL VARIABLES:
+!
+    INTEGER :: HH, MM, SS, SECS, OFFSET
+
+    !==================================================================
+    ! Compute first I-6 time for all met field types
+    !==================================================================
+
+    ! Split NYMS into hours, mins, seconds
+    CALL YMD_EXTRACT( NHMS, HH, MM, SS )
+
+    ! Compute seconds elapsed in the 3-hour interval
+    SECS   = MOD( HH, 1 )*3600 + MM*60 + SS
+
+    ! Compute offset to nearest I-6 time
+    OFFSET = -SECS
+
+    ! Get YYYY/MM/DD and hh:mm:ss to nearest I-6 time
+    DATE   = GET_TIME_AHEAD( OFFSET )
+
+  END FUNCTION GET_FIRST_I1dyn_TIME
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
 ! !IROUTINE: Get_first_bc_time
 !
 ! !DESCRIPTION: Function GET\_FIRST\_BC\_TIME returns the correct YYYYMMDD and
@@ -2371,6 +2497,43 @@ END FUNCTION ITS_TIME_FOR_I3
 !------------------------------------------------------------------------------
 !BOP
 !
+! !IROUTINE: Its_Time_For_i1dyn
+!
+! !DESCRIPTION: Function ITS\_TIME\_FOR\_I1dyn returns TRUE if it is time to read
+!  in I1 (instantaneous 1-hr fields) and FALSE otherwise.
+!\\
+!\\
+! !INTERFACE:
+!
+  FUNCTION ITS_TIME_FOR_I1dyn() RESULT( FLAG )
+!
+! !RETURN VALUE:
+!
+    LOGICAL :: FLAG
+!
+! !REVISION HISTORY:
+!  15 Jun 2024 - X. Wang - Initial version, for 0.125x0.15625
+!  See https://github.com/geoschem/geos-chem for complete history
+!EOP
+!------------------------------------------------------------------------------
+!BOC
+!
+! !LOCAL VARAIABLES:
+!
+    LOGICAL, SAVE :: FIRST = .TRUE.
+
+    ! We read in I1dyn fields every hours at 00, 01, 02, ... GMT
+    FLAG = ( ( MOD( NHMS, 10000 ) == 0 ) .or. FIRST )
+
+    FIRST = .FALSE.
+
+  END FUNCTION ITS_TIME_FOR_I1dyn
+!EOC
+!------------------------------------------------------------------------------
+!                  GEOS-Chem Global Chemical Transport Model                  !
+!------------------------------------------------------------------------------
+!BOP
+!
 ! !IROUTINE: Its_Time_For_bc
 !
 ! !DESCRIPTION: Function ITS\_TIME\_FOR\_BC returns TRUE if it is time to read
diff --git a/Interfaces/GCClassic/main.F90 b/Interfaces/GCClassic/main.F90
index 6a0c87ff0..e343b7590 100644
--- a/Interfaces/GCClassic/main.F90
+++ b/Interfaces/GCClassic/main.F90
@@ -1867,13 +1867,29 @@ PROGRAM GEOS_Chem
        !=====================================================================
        IF ( notDryRun ) THEN
           IF ((mod(get_hour(), 3) .eq. 0) .AND. (get_minute() .eq. 0)) THEN
-             CALL Copy_I3_Fields( State_Met )
+             CALL Copy_I3_Fields( State_Met, State_Grid )
              IF ( VerboseAndRoot ) THEN
                 CALL Debug_Msg( '### MAIN: after COPY_I3_FIELDS' )
              ENDIF
           ENDIF
        ENDIF
 
+       !=====================================================================
+       !            ***** C O P Y   I - 1 d y n   F I E L D S *****
+       !
+       ! The I-1 fields at the end of an outer timestep (every 1 hours)
+       ! become the fields at the beginning of the next timestep.
+       ! This update must occur before writing History.
+       !=====================================================================
+       IF ( notDryRun .and. TRIM(State_Grid%GridRes) == '0.125x0.15625' ) THEN
+          IF ((mod(get_hour(), 1) .eq. 0) .AND. (get_minute() .eq. 0)) THEN
+             CALL Copy_I1dyn_Fields( State_Met )
+             IF ( VerboseAndRoot ) THEN
+                CALL Debug_Msg( '### MAIN: after COPY_I1dyn_FIELDS' )
+             ENDIF
+          ENDIF
+       ENDIF
+
        !---------------------------------------------------------------------
        !               ***** H I S T O R Y   W R I T E *****
        !---------------------------------------------------------------------
diff --git a/run/GCClassic/HEMCO_Config.rc.templates/HEMCO_Config.rc.gmao_metfields_0125 b/run/GCClassic/HEMCO_Config.rc.templates/HEMCO_Config.rc.gmao_metfields_0125
new file mode 100644
index 000000000..e7dc79ebe
--- /dev/null
+++ b/run/GCClassic/HEMCO_Config.rc.templates/HEMCO_Config.rc.gmao_metfields_0125
@@ -0,0 +1,154 @@
+#------------------------------------------------------------------------------
+#                  Harmonized Emissions Component (HEMCO)                     !
+#------------------------------------------------------------------------------
+#BOP
+#
+# !MODULE: HEMCO_Config.rc
+#
+# !DESCRIPTION: Contains configuration information for GMAO meteorology fields
+#  in HEMCO.
+#\\
+#\\
+# !REMARKS:
+#  See The HEMCO User's Guide for file details:
+#    http://wiki.geos-chem.org/The_HEMCO_User%27s_Guide
+#
+# !REVISION HISTORY:
+#  See https://github.com/geoschem/geos-chem for complete history
+#EOP
+#------------------------------------------------------------------------------
+#BOC
+###############################################################################
+### BEGIN SECTION SETTINGS
+###############################################################################
+
+ROOT:        ${RUNDIR_DATA_ROOT}/HEMCO
+METDIR:      ${RUNDIR_DATA_ROOT}/GEOS_0.25x0.3125/GEOS_FP
+HIGHRES:     ${RUNDIR_MET_DIR}
+
+### END SECTION SETTINGS ###
+
+###############################################################################
+### BEGIN SECTION BASE EMISSIONS
+###############################################################################
+
+# ExtNr	Name sourceFile	sourceVar sourceTime C/R/E SrcDim SrcUnit Species ScalIDs Cat Hier
+
+#==============================================================================
+# --- Meteorology fields ---
+#==============================================================================
+
+# --- CN fields ---
+* FRLAKE    $METDIR/$CNYR/01/$MET.$CNYR0101.CN.025x03125.NA.$NC        FRLAKE   */1/1/0               C xy  1  * -  1 1
+* FRLAND    $METDIR/$CNYR/01/$MET.$CNYR0101.CN.025x03125.NA.$NC        FRLAND   */1/1/0               C xy  1  * -  1 1
+* FRLANDIC  $METDIR/$CNYR/01/$MET.$CNYR0101.CN.025x03125.NA.$NC        FRLANDIC */1/1/0               C xy  1  * -  1 1
+* FROCEAN   $METDIR/$CNYR/01/$MET.$CNYR0101.CN.025x03125.NA.$NC        FROCEAN  */1/1/0               C xy  1  * -  1 1
+* PHIS      $METDIR/$CNYR/01/$MET.$CNYR0101.CN.025x03125.NA.$NC        PHIS     */1/1/0               C xy  1  * -  1 1
+
+# --- A1 fields ---
+* ALBEDO    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     ALBEDO   1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* CLDTOT    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     CLDTOT   1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* EFLUX     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     EFLUX    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* EVAP      $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     EVAP     1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* FRSEAICE  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     FRSEAICE 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* FRSNO     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     FRSNO    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* GRN       $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     GRN      1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* GWETROOT  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     GWETROOT 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* GWETTOP   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     GWETTOP  1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* HFLUX     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     HFLUX    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* LAI       $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     LAI      1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* LWGNT     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     LWGNT    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PARDF     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PARDF    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PARDR     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PARDR    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PBLH      $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PBLH     1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PRECANV   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PRECANV  1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PRECCON   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PRECCON  1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PRECLSC   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PRECLSC  1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PRECSNO   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PRECSNO  1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* PRECTOT   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     PRECTOT  1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* QV2M      $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     QV2M     1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE00  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE00 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE10  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE10 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE20  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE20 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE30  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE30 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE40  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE40 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE50  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE50 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE60  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE60 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE70  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE70 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE80  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE80 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SEAICE90  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SEAICE90 1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SLP       $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SLP      1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SNODP     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SNODP    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SNOMAS    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SNOMAS   1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* SWGDN     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     SWGDN    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* TO3       $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     TO3      1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* TROPPT    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     TROPPT   1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* TS        $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     TS       1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* T2M       $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     T2M      1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* U10M      $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     U10M     1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* USTAR     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     USTAR    1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* V10M      $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     V10M     1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+* Z0M       $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A1.025x03125.NA.$NC     Z0M      1980-2021/1-12/1-31/*/+30minute EFY xy  1  * -  1 1
+
+# --- A3cld fields ---
+* CLOUD     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3cld.025x03125.NA.$NC  CLOUD    1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* OPTDEPTH  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3cld.025x03125.NA.$NC  OPTDEPTH 1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* QI        $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3cld.025x03125.NA.$NC  QI       1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* QL        $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3cld.025x03125.NA.$NC  QL       1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* TAUCLI    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3cld.025x03125.NA.$NC  TAUCLI   1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* TAUCLW    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3cld.025x03125.NA.$NC  TAUCLW   1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+
+# --- A3dyn fields ---
+* DTRAIN    $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3dyn.025x03125.NA.$NC  DTRAIN   1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* OMEGA     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3dyn.025x03125.NA.$NC  OMEGA    1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* RH        $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3dyn.025x03125.NA.$NC  RH       1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+
+# --- A3mstC fields ---
+* DQRCU     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstC.025x03125.NA.$NC DQRCU    1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* DQRLSAN   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstC.025x03125.NA.$NC DQRLSAN  1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* REEVAPCN  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstC.025x03125.NA.$NC REEVAPCN 1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* REEVAPLS  $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstC.025x03125.NA.$NC REEVAPLS 1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+
+# --- A3mstE fields ---
+* CMFMC     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstE.025x03125.NA.$NC CMFMC    1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* PFICU     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstE.025x03125.NA.$NC PFICU    1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* PFILSAN   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstE.025x03125.NA.$NC PFILSAN  1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* PFLCU     $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstE.025x03125.NA.$NC PFLCU    1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+* PFLLSAN   $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.A3mstE.025x03125.NA.$NC PFLLSAN  1980-2021/1-12/1-31/*/+90minute EFY xyz 1  * -  1 1
+
+# --- I3 fields ---
+* TMPU         $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.I3.025x03125.NA.$NC T         1980-2021/1-12/1-31/*           EFY xyz 1  * -  1 1
+* TMPU_NEXTDAY $METDIR/$YYYY/$MM/$MET.$YYYY$MM$DD.I3.025x03125.NA.$NC T         1980-2021/1-12/1-31/1/+1day     EFY xyz 1  * -  1 1
+
+# --- 0.125x0.15625 fields ---
+* U            $HIGHRES/Y$YYYY/M$MM/D$DD/GEOS.fp.asm.A1dyn.0125x015625.NA.$YYYY$MM$DD.nc4  UA  2021-2023/1-12/1-31/*           EFY xyz 1  * -  1 1
+* V            $HIGHRES/Y$YYYY/M$MM/D$DD/GEOS.fp.asm.A1dyn.0125x015625.NA.$YYYY$MM$DD.nc4  VA  2021-2023/1-12/1-31/*           EFY xyz 1  * -  1 1
+* PS           $HIGHRES/Y$YYYY/M$MM/D$DD/GEOS.fp.asm.I1dyn.0125x015625.NA.$YYYY$MM$DD.nc4  PS  2021-2023/1-12/1-31/*           EFY xy  1  * -  1 1
+* SPHU         $HIGHRES/Y$YYYY/M$MM/D$DD/GEOS.fp.asm.I1dyn.0125x015625.NA.$YYYY$MM$DD.nc4  QV  2021-2023/1-12/1-31/*           EFY xyz 1  * -  1 1
+
+* PS_NEXTDAY   $HIGHRES/Y$YYYY/M$MM/D$DD/GEOS.fp.asm.I1dyn.0125x015625.NA.$YYYY$MM$DD.nc4  PS  2021-2023/1-12/1-31/*/+1day     EFY xy  1  * -  1 1
+* SPHU_NEXTDAY $HIGHRES/Y$YYYY/M$MM/D$DD/GEOS.fp.asm.I1dyn.0125x015625.NA.$YYYY$MM$DD.nc4  QV  2021-2023/1-12/1-31/*/+1day     EFY xyz 1  * -  1 1
+
+#==============================================================================
+# --- Fields for lightning emissions (Extension 103) ---
+#
+# Native-resolution lightning flash rates constrained to LIS/OTD climatology
+# and convective depth are now prescribed as offline meteorology.
+#                                                    --Lee Murray (16 Jan 2019)
+#==============================================================================
+(((LightNOx
+(((.not.LightningClimatology
+* FLASH_DENS $ROOT/OFFLINE_LIGHTNING/v2020-03/$MET/$YYYY/FLASH_CTH_$MET_0.25x0.3125_$YYYY_$MM.nc4  LDENS 1980-2021/1-12/1-31/0-23/+90minute RFY3 xy  1  * -  1 1
+* CONV_DEPTH $ROOT/OFFLINE_LIGHTNING/v2020-03/$MET/$YYYY/FLASH_CTH_$MET_0.25x0.3125_$YYYY_$MM.nc4  CTH   1980-2021/1-12/1-31/0-23/+90minute RFY3 xy  1  * -  1 1
+))).not.LightningClimatology
+
+(((LightningClimatology
+* FLASH_DENS $ROOT/OFFLINE_LIGHTNING/v2020-03/$MET/CLIM/FLASH_CTH_$MET_0.25x0.3125_2014-2019.ymonmean.nc4  LDENS 2019/1-12/1/0 C xy  1  * -  1 1
+* CONV_DEPTH $ROOT/OFFLINE_LIGHTNING/v2020-03/$MET/CLIM/FLASH_CTH_$MET_0.25x0.3125_2014-2019.ymonmean.nc4  CTH   2019/1-12/1/0 C xy  1  * -  1 1
+)))LightningClimatology
+)))LightNOx
+
+### END SECTION BASE EMISSIONS ###
+
+### END OF HEMCO INPUT FILE ###
+#EOC
\ No newline at end of file
diff --git a/run/GCClassic/createRunDir.sh b/run/GCClassic/createRunDir.sh
index 9594d89c0..3ce2c55cd 100755
--- a/run/GCClassic/createRunDir.sh
+++ b/run/GCClassic/createRunDir.sh
@@ -533,6 +533,7 @@ else
     printf "  3. 0.5  x 0.625\n"
     if [[ "x${met}" == "xgeosfp" ]]; then
 	printf "  4. 0.25 x 0.3125\n"
+	printf "  5. 0.125 x 0.15625\n"
     fi
 fi
 
@@ -550,8 +551,6 @@ while [ "${valid_res}" -eq 0 ]; do
 	grid_res='05x0625'
 	RUNDIR_VARS+="$(cat ${gcdir}/run/shared/settings/05x0625.txt)\n"
     elif [[ "x${res_num}" == "x4" ]]; then
-	# Error check: Don't allow a 0.25 x 0.3125 MERRA-2 rundir.
-	#  -- Melissa Sulprizio, Bob Yantosca (12 Sep 2023)
 	if [[ "x${met}" == "xmerra2" ]]; then
 	    valid_res=0
 	    printf "Cannot create a MERRA-2 rundir at 0.25 x 0.3125 "
@@ -559,6 +558,15 @@ while [ "${valid_res}" -eq 0 ]; do
 	fi
 	grid_res='025x03125'
 	RUNDIR_VARS+="$(cat ${gcdir}/run/shared/settings/025x03125.txt)\n"
+    elif [[ "x${res_num}" == "x5" ]]; then
+	if [[ "x${met}" == "xmerra2" ]]; then
+	    valid_res=0
+	    printf "Cannot create a MERRA-2 rundir at 0.125 x 0.15625 "
+	    printf "resolution!\nPlease make another selection.\n"
+	fi
+	grid_res='0125x015625'
+	RUNDIR_VARS+="$(cat ${gcdir}/run/shared/settings/0125x015625.txt)\n"
+	RUNDIR_VARS+="RUNDIR_MET_FIELD_CONFIG='HEMCO_Config.rc.gmao_metfields_0125'\n"
     else
 	valid_res=0
 	printf "Invalid horizontal resolution option.\n"
@@ -566,7 +574,7 @@ while [ "${valid_res}" -eq 0 ]; do
     fi
 done
 
-if [[ "${met}" != "geosit" ]] && [[ "${grid_res}" = "05x0625" || "${grid_res}" = "025x03125" ]]; then
+if [[ "${met}" != "geosit" ]] && [[ "${grid_res}" = "05x0625" || "${grid_res}" = "025x03125" ]] || [[ ${grid_res} = "0125x015625" ]]; then
     printf "${thinline}Choose horizontal grid domain:${thinline}"
     printf "  1. Global\n"
     printf "  2. Asia\n"
@@ -589,7 +597,7 @@ if [[ "${met}" != "geosit" ]] && [[ "${grid_res}" = "05x0625" || "${grid_res}" =
 	        if [[ ${grid_res} = "05x0625" ]]; then
 	            RUNDIR_VARS+="RUNDIR_GRID_LON_RANGE='[ 60.0, 150.0]'\n"
 		    RUNDIR_VARS+="RUNDIR_GRID_LAT_RANGE='[-11.0,  55.0]'\n"
-		elif [[ ${grid_res} = "025x03125" ]]; then
+		elif [[ ${grid_res} = "025x03125" ]] || [[ ${grid_res} = "0125x015625" ]]; then
 	            RUNDIR_VARS+="RUNDIR_GRID_LON_RANGE='[ 70.0, 140.0]'\n"
 		    RUNDIR_VARS+="RUNDIR_GRID_LAT_RANGE='[ 15.0,  55.0]'\n"
 		fi
@@ -599,7 +607,7 @@ if [[ "${met}" != "geosit" ]] && [[ "${grid_res}" = "05x0625" || "${grid_res}" =
 	        if [[ ${grid_res} = "05x0625" ]]; then
 	            RUNDIR_VARS+="RUNDIR_GRID_LON_RANGE='[-30.0, 50.0]'\n"
 		    RUNDIR_VARS+="RUNDIR_GRID_LAT_RANGE='[ 30.0, 70.0]'\n"
-		elif [[ ${grid_res} = "025x03125" ]]; then
+		elif [[ ${grid_res} = "025x03125" ]] || [[ ${grid_res} = "0125x015625" ]]; then
 	            RUNDIR_VARS+="RUNDIR_GRID_LON_RANGE='[-15.0,  40.0 ]'\n"
 		    RUNDIR_VARS+="RUNDIR_GRID_LAT_RANGE='[ 32.75, 61.25]'\n"
 		fi
@@ -609,7 +617,7 @@ if [[ "${met}" != "geosit" ]] && [[ "${grid_res}" = "05x0625" || "${grid_res}" =
 	        if [[ ${grid_res} = "05x0625" ]]; then
 	            RUNDIR_VARS+="RUNDIR_GRID_LON_RANGE='[-140.0, -40.0]'\n"
 		    RUNDIR_VARS+="RUNDIR_GRID_LAT_RANGE='[  10.0,  70.0]'\n"
-		elif [[ ${grid_res} = "025x03125" ]]; then
+		elif [[ ${grid_res} = "025x03125" ]] || [[ ${grid_res} = "0125x015625" ]]; then
 	            RUNDIR_VARS+="RUNDIR_GRID_LON_RANGE='[-130.0,  -60.0]'\n"
 		    RUNDIR_VARS+="RUNDIR_GRID_LAT_RANGE='[   9.75,  60.0]'\n"
 		fi
@@ -643,7 +651,7 @@ fi
 RUNDIR_VARS+="$(cat ${shared_met_settings})\n"   # shared_met_settings needs to be included after RUNDIR_GRID_DIR is defined
 
 # Set timesteps according to grid resolution
-if [[ ${grid_res} = "05x0625" ]] || [[ ${grid_res} = "025x03125" ]]; then
+if [[ ${grid_res} = "05x0625" ]] || [[ ${grid_res} = "025x03125" ]] || [[ ${grid_res} = "0125x015625" ]]; then
     RUNDIR_VARS+="RUNDIR_TRANSPORT_TS='300'\n"
     RUNDIR_VARS+="RUNDIR_CHEMISTRY_TS='600'\n"
 else
diff --git a/run/shared/settings/0125x015625.txt b/run/shared/settings/0125x015625.txt
new file mode 100644
index 000000000..79f244a66
--- /dev/null
+++ b/run/shared/settings/0125x015625.txt
@@ -0,0 +1,3 @@
+RUNDIR_GRID_RES='0125x015625'
+RUNDIR_GRID_RES_LONG='0.125x0.15625'
+RUNDIR_GRID_DIR='0.125x0.15625'