Merge branch 'rfiorella/lnd/add-era5-to-couplerbypass' (PR #7480)

As noted in #7428, many of the datm timeseries that can be passed through the current coupler bypass end ~10 years ago.
This PR adds a few lines to add a new data source for ERA5 to this module.

Fixes #7428

[BFB] tested on local systems.

Author: peterdschwartz

components/elm/src/cpl/lnd_import_export.F90

@@ -47,8 +47,8 @@ subroutine lnd_import( bounds, x2l, atm2lnd_vars, glc2lnd_vars, lnd2atm_vars)
     ! !ARGUMENTS:
     type(bounds_type)  , intent(in)    :: bounds   ! bounds
     real(r8)           , intent(in)    :: x2l(:,:) ! driver import state to land model
-    type(atm2lnd_type) , intent(inout) :: atm2lnd_vars      ! clm internal input data type
-    type(glc2lnd_type) , intent(inout) :: glc2lnd_vars      ! clm internal input data type
+    type(atm2lnd_type) , intent(inout) :: atm2lnd_vars      ! elm internal input data type
+    type(glc2lnd_type) , intent(inout) :: glc2lnd_vars      ! elm internal input data type
     type(lnd2atm_type) , intent(in)    :: lnd2atm_vars
     !
     ! !LOCAL VARIABLES:
@@ -236,6 +236,8 @@ subroutine lnd_import( bounds, x2l, atm2lnd_vars, glc2lnd_vars, lnd2atm_vars)
             atm2lnd_vars%metsource = 4
           else if (index(metdata_type,'cpl') .gt. 0) then 
             atm2lnd_vars%metsource = 5
+          else if (index(metdata_type,'era5') .gt. 0) then
+            atm2lnd_vars%metsource = 6
           else
             call endrun( sub//' ERROR: Invalid met data source for cpl_bypass' )
           end if
@@ -306,6 +308,10 @@ subroutine lnd_import( bounds, x2l, atm2lnd_vars, glc2lnd_vars, lnd2atm_vars)
             atm2lnd_vars%startyear_met      = 566 !76
             atm2lnd_vars%endyear_met_spinup = 590 !100
             atm2lnd_vars%endyear_met_trans  = 590 !100
+          else if (atm2lnd_vars%metsource == 6) then
+            atm2lnd_vars%startyear_met      = 1950
+            atm2lnd_vars%endyear_met_spinup = 1970
+            atm2lnd_vars%endyear_met_trans  = 2025
           end if
 
           if (use_livneh) then 
@@ -404,6 +410,8 @@ subroutine lnd_import( bounds, x2l, atm2lnd_vars, glc2lnd_vars, lnd2atm_vars)
             else if (atm2lnd_vars%metsource == 5) then 
                     !metdata_fname = 'WCYCL1850S.ne30_' // trim(metvars(v)) // '_0076-0100_z' // zst(2:3) // '.nc'
                     metdata_fname = 'CBGC1850S.ne30_' // trim(metvars(v)) // '_0566-0590_z' // zst(2:3) // '.nc'
+            else if (atm2lnd_vars%metsource == 6) then
+                metdata_fname = 'ERA5_' // trim(metvars(v)) // '_1950-2025_z' // zst(2:3) // '.nc'
             end if
 
             ierr = nf90_open(trim(metdata_bypass) // '/' // trim(metdata_fname), NF90_NOWRITE, met_ncids(v))
@@ -500,22 +508,29 @@ subroutine lnd_import( bounds, x2l, atm2lnd_vars, glc2lnd_vars, lnd2atm_vars)
           end do    !end variable loop        
         else
           do v=1,met_nvars
-            if (atm2lnd_vars%npf(v) - 1._r8 .gt. 1e-3) then 
+            if (atm2lnd_vars%npf(v) - 1._r8 .gt. 1e-3) then
               if (v .eq. 4 .or. v .eq. 5 .or. (v .ge. 8 .and. v .le. 13)) then    !rad/Precipitation
                 if (mod(tod/get_step_size(),nint(atm2lnd_vars%npf(v))) == 1 .and. nstep .gt. 3) then
                   atm2lnd_vars%tindex(g,v,1) = atm2lnd_vars%tindex(g,v,1)+1
                   atm2lnd_vars%tindex(g,v,2) = atm2lnd_vars%tindex(g,v,2)+1
                 end if
-              else  
-                if (mod(tod/get_step_size()-1,nint(atm2lnd_vars%npf(v))) <= atm2lnd_vars%npf(v)/2._r8 .and. &
-                    mod(tod/get_step_size(),nint(atm2lnd_vars%npf(v))) > atm2lnd_vars%npf(v)/2._r8) then 
-                  atm2lnd_vars%tindex(g,v,1) = atm2lnd_vars%tindex(g,v,1)+1
-                  atm2lnd_vars%tindex(g,v,2) = atm2lnd_vars%tindex(g,v,2)+1
+              else
+                if (atm2lnd_vars%npf(v) .ne. 2._r8) then
+                  if (mod(tod/get_step_size()-1,nint(atm2lnd_vars%npf(v))) <= atm2lnd_vars%npf(v)/2._r8 .and. &
+                      mod(tod/get_step_size(),nint(atm2lnd_vars%npf(v))) > atm2lnd_vars%npf(v)/2._r8) then
+                    atm2lnd_vars%tindex(g,v,1) = atm2lnd_vars%tindex(g,v,1)+1
+                    atm2lnd_vars%tindex(g,v,2) = atm2lnd_vars%tindex(g,v,2)+1
+                  end if
+                else
+                  if (mod(tod/get_step_size(),nint(atm2lnd_vars%npf(v))) == 1 .and. nstep .gt. 3) then
+                     atm2lnd_vars%tindex(g,v,1) = atm2lnd_vars%tindex(g,v,1)+1
+                     atm2lnd_vars%tindex(g,v,2) = atm2lnd_vars%tindex(g,v,2)+1
+                  end if
                 end if
               end if
             else
               atm2lnd_vars%tindex(g,v,1) = atm2lnd_vars%tindex(g,v,1)+nint(1/atm2lnd_vars%npf(v))
-              atm2lnd_vars%tindex(g,v,2) = atm2lnd_vars%tindex(g,v,2)+nint(1/atm2lnd_vars%npf(v))  
+              atm2lnd_vars%tindex(g,v,2) = atm2lnd_vars%tindex(g,v,2)+nint(1/atm2lnd_vars%npf(v))
             end if
 
             if (const_climate_hist .or. yr .le. atm2lnd_vars%startyear_met) then
@@ -1377,8 +1392,8 @@ subroutine lnd_export( bounds, lnd2atm_vars, lnd2glc_vars, l2x)
     ! !ARGUMENTS:
     implicit none
     type(bounds_type) , intent(in)    :: bounds  ! bounds
-    type(lnd2atm_type), intent(inout) :: lnd2atm_vars ! clm land to atmosphere exchange data type
-    type(lnd2glc_type), intent(inout) :: lnd2glc_vars ! clm land to atmosphere exchange data type
+    type(lnd2atm_type), intent(inout) :: lnd2atm_vars ! elm land to atmosphere exchange data type
+    type(lnd2glc_type), intent(inout) :: lnd2glc_vars ! elm land to atmosphere exchange data type
     real(r8)          , intent(out)   :: l2x(:,:)! land to coupler export state on land grid
     !
     ! !LOCAL VARIABLES: