diff --git a/dyn_em/module_big_step_utilities_em.F b/dyn_em/module_big_step_utilities_em.F
index 72e827b275..96d0c3c26a 100644
--- a/dyn_em/module_big_step_utilities_em.F
+++ b/dyn_em/module_big_step_utilities_em.F
@@ -2,7 +2,7 @@
 !wrf:MODEL_LAYER:DYNAMICS
 !
 
-#if (RWORDSIZE == 4)
+#ifndef DOUBLE_PRECISION
 # define VPOWX vspowx
 # define VPOW  vspow
 #else
diff --git a/frame/module_clear_halos.F b/frame/module_clear_halos.F
index 88de325ecf..db19e0e5fc 100644
--- a/frame/module_clear_halos.F
+++ b/frame/module_clear_halos.F
@@ -42,7 +42,7 @@ subroutine clear_ij_halos(grid,how,full_domain)
          ips, ipe, jps, jpe, kps, kpe
     logical :: fulldom
     real :: badR, badR_N,badR_NE,badR_NW,badR_S,badR_SW,badR_SE,badR_E,badR_W
-#if (RWORDSIZE==4)
+#ifndef DOUBLE_PRECISION
     double precision :: badD, badD_N,badD_NE,badD_NW,badD_S,badD_SW,badD_SE,badD_E,badD_W
 #else
     real             :: badD, badD_N,badD_NE,badD_NW,badD_S,badD_SW,badD_SE,badD_E,badD_W
diff --git a/phys/ccpp_kind_types.F b/phys/ccpp_kind_types.F
index 9360bbf67e..5647ce0362 100644
--- a/phys/ccpp_kind_types.F
+++ b/phys/ccpp_kind_types.F
@@ -1,5 +1,5 @@
 module ccpp_kind_types
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
    integer, parameter :: kind_phys = selected_real_kind(6)
 #else
    integer, parameter :: kind_phys = selected_real_kind(12)
diff --git a/phys/module_mp_wdm5.F b/phys/module_mp_wdm5.F
index 6e69b082e2..0e67a665c6 100644
--- a/phys/module_mp_wdm5.F
+++ b/phys/module_mp_wdm5.F
@@ -1,4 +1,4 @@
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wdm6.F b/phys/module_mp_wdm6.F
index 4509fff847..e30ec5ade9 100644
--- a/phys/module_mp_wdm6.F
+++ b/phys/module_mp_wdm6.F
@@ -1,4 +1,4 @@
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wdm7.F b/phys/module_mp_wdm7.F
index d29374481c..9096c997e5 100644
--- a/phys/module_mp_wdm7.F
+++ b/phys/module_mp_wdm7.F
@@ -1,4 +1,4 @@
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wsm3.F b/phys/module_mp_wsm3.F
index a71d3cbfa6..0081a4817e 100644
--- a/phys/module_mp_wsm3.F
+++ b/phys/module_mp_wsm3.F
@@ -1,7 +1,7 @@
 #ifdef _ACCEL
 #  include "module_mp_wsm3_accel.F"
 #else
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wsm3_accel.F b/phys/module_mp_wsm3_accel.F
index bacec9bfad..21c7a7e00e 100644
--- a/phys/module_mp_wsm3_accel.F
+++ b/phys/module_mp_wsm3_accel.F
@@ -1,4 +1,4 @@
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wsm5.F b/phys/module_mp_wsm5.F
index e081a7b6e4..c80978e702 100644
--- a/phys/module_mp_wsm5.F
+++ b/phys/module_mp_wsm5.F
@@ -1,7 +1,7 @@
 #ifdef _ACCEL
 #  include "module_mp_wsm5_accel.F"
 #else
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wsm5_accel.F b/phys/module_mp_wsm5_accel.F
index 085ef2f441..286e6a14cd 100644
--- a/phys/module_mp_wsm5_accel.F
+++ b/phys/module_mp_wsm5_accel.F
@@ -1,4 +1,4 @@
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_mp_wsm7.F b/phys/module_mp_wsm7.F
index 8f757f08c5..9b0c777d47 100644
--- a/phys/module_mp_wsm7.F
+++ b/phys/module_mp_wsm7.F
@@ -1,4 +1,4 @@
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
 #  define VREC vsrec
 #  define VSQRT vssqrt
 #else
diff --git a/phys/module_ra_goddard.F b/phys/module_ra_goddard.F
index f9387c1a92..fd1118cac2 100644
--- a/phys/module_ra_goddard.F
+++ b/phys/module_ra_goddard.F
@@ -2062,7 +2062,7 @@ subroutine goddardrad( sw_or_lw, dx    &
       ENDDO
 
 
-#if (RWORDSIZE == 4)
+#ifndef DOUBLE_PRECISION
       call swrad ( np=dk_half, icb=icb, ict=ict, fcld=dble(fcld1d), &
                    pl=dble(p8w1d), ta=dble(t1d), wa=dble(sh1d), oa=dble(o31d), &
                    taucl=dble(taucl_sw), ssacl=dble(ssacl_sw), asycl=dble(asycl_sw), &
@@ -2312,7 +2312,7 @@ subroutine goddardrad( sw_or_lw, dx    &
 ! 1-dimension driver of longwave radiative transfer scheme
 !
 
-#if (RWORDSIZE == 4)
+#ifndef DOUBLE_PRECISION
        call lwrad ( np=dk_half, tb=dble(tsfc), ts=dble(tskin), ict=ict, icb=icb,&
                     pl=dble(p8w1d), ta=dble(t1d), wa=dble(sh1d), oa=dble(o31d), &
                     emiss=dble(emis1d), fcld=dble(fcld1d), &
diff --git a/phys/module_ra_rrtmg_lw.F b/phys/module_ra_rrtmg_lw.F
index 6b5dc2d342..061af5ab26 100644
--- a/phys/module_ra_rrtmg_lw.F
+++ b/phys/module_ra_rrtmg_lw.F
@@ -35,7 +35,7 @@ module parkind
 #if (RWORDSIZE == 8)
       integer, parameter :: kind_rb = selected_real_kind(12) ! 8 byte real
 #endif
-#if (RWORDSIZE == 4)
+#ifndef DOUBLE_PRECISION
       integer, parameter :: kind_rb = selected_real_kind(6)  ! 4 byte real
 #endif
 #else
diff --git a/var/da/da_obs_io/da_read_obs_bufr.inc b/var/da/da_obs_io/da_read_obs_bufr.inc
index ca29ceada9..60098764aa 100644
--- a/var/da/da_obs_io/da_read_obs_bufr.inc
+++ b/var/da/da_obs_io/da_read_obs_bufr.inc
@@ -542,7 +542,7 @@ bufrfile:  do ibufr=1,numbufr
       end if
       if ( obs(7,1) < r8bfms ) then
          pwq=nint(qms(7,1))
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
          pwe = min(DBLE(err_pw), oes(7,1))
 #else
          pwe = min(err_pw, oes(7,1))
@@ -604,7 +604,7 @@ bufrfile:  do ibufr=1,numbufr
          !Not currently used
          !cat=nint(obs(8,k))
 
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
          toe = min(DBLE(err_t), oes(3,k))
          woe = min(DBLE(err_uv), oes(5,k))
          qoe = min(DBLE(err_q), oes(2,k)*10.0)  ! convert to % from PREPBUFR percent divided by 10
@@ -686,7 +686,7 @@ bufrfile:  do ibufr=1,numbufr
 
       ! assign u,v,t,q obs errors for synop and metar
       if ( t29 == 512 .or. t29 == 511 .or. t29 == 514 ) then
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
          toe = min(DBLE(err_t), oes(3,1))
          woe = min(DBLE(err_uv), oes(5,1))
          qoe = min(DBLE(err_q), oes(2,1)*10.0)  ! convert to % from PREPBUFR percent divided by 10
diff --git a/var/da/da_par_util/da_proc_maxmin_combine.inc b/var/da/da_par_util/da_proc_maxmin_combine.inc
index bd3fe40d13..141586ad9e 100644
--- a/var/da/da_par_util/da_proc_maxmin_combine.inc
+++ b/var/da/da_par_util/da_proc_maxmin_combine.inc
@@ -32,7 +32,7 @@ subroutine da_proc_maxmin_combine(n, max, min)
       in(2*i)   = myproc
    end do
 
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
    call mpi_reduce(in, out, n, mpi_2real, mpi_minloc, root, comm, ierr)
 #else
    call mpi_reduce(in, out, n, mpi_2double_precision, mpi_minloc, root, comm, ierr)
@@ -65,7 +65,7 @@ subroutine da_proc_maxmin_combine(n, max, min)
       in(2*i-1) = max(i)%value
       in(2*i)   = myproc
    end do
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
    call mpi_reduce(in, out, n, mpi_2real, mpi_maxloc, root, comm, ierr)
 #else
    call mpi_reduce(in, out, n, mpi_2double_precision, mpi_maxloc, root, comm, ierr)
diff --git a/var/da/da_par_util/da_proc_stats_combine.inc b/var/da/da_par_util/da_proc_stats_combine.inc
index d8fd895f57..74573c9300 100644
--- a/var/da/da_par_util/da_proc_stats_combine.inc
+++ b/var/da/da_par_util/da_proc_stats_combine.inc
@@ -43,7 +43,7 @@ subroutine da_proc_stats_combine(proc_ave, proc_err, proc_min, proc_max, &
    ! Get minimum value and associated processor index.
    in(1) = proc_min
    in(2) = myproc
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
    call mpi_reduce(in, out, 1, mpi_2real, mpi_minloc, root, comm, ierr)
 #else
    call mpi_reduce(in, out, 1, mpi_2double_precision, mpi_minloc, root, comm, ierr)
@@ -73,7 +73,7 @@ subroutine da_proc_stats_combine(proc_ave, proc_err, proc_min, proc_max, &
    in(1) = proc_max
    in(2) = myproc
 
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
    call mpi_reduce(in, out, 1, mpi_2real, mpi_maxloc, root, comm, ierr)
 #else
    call mpi_reduce(in, out, 1, mpi_2double_precision, mpi_maxloc, root, comm, ierr)
diff --git a/var/da/da_radiance/gsi_kinds.f90 b/var/da/da_radiance/gsi_kinds.f90
index 0c0ac7c27c..672a43fb5d 100644
--- a/var/da/da_radiance/gsi_kinds.f90
+++ b/var/da/da_radiance/gsi_kinds.f90
@@ -96,7 +96,7 @@ module gsi_kinds
 ! Default values
 ! **** CHANGE THE FOLLOWING TO CHANGE THE DEFAULT REAL TYPE KIND ***
 ! 1=single, 2=double, 3=quad
-#if ( RWORDSIZE == 4 )
+#ifndef DOUBLE_PRECISION
   integer, parameter, private :: default_real = 1
 #else
   integer, parameter, private :: default_real = 2
diff --git a/wrftladj/module_big_step_utilities_em_ad.F b/wrftladj/module_big_step_utilities_em_ad.F
index 8cc13725e9..b4f42ca6b7 100644
--- a/wrftladj/module_big_step_utilities_em_ad.F
+++ b/wrftladj/module_big_step_utilities_em_ad.F
@@ -11,7 +11,7 @@ MODULE a_module_big_step_utilities_em
    kfetascheme, mskfscheme, g3scheme, p_qv, param_first_scalar, p_qr, p_qc, DFI_FWD
    USE module_configure, ONLY : grid_config_rec_type
    USE module_wrf_error
-#if (RWORDSIZE == 4)
+#ifndef DOUBLE_PRECISION
 #   define VPOWX vspowx
 #   define VPOW  vspow
 #else
diff --git a/wrftladj/module_big_step_utilities_em_tl.F b/wrftladj/module_big_step_utilities_em_tl.F
index cab1e5e525..67d79f9b7d 100644
--- a/wrftladj/module_big_step_utilities_em_tl.F
+++ b/wrftladj/module_big_step_utilities_em_tl.F
@@ -5,7 +5,7 @@
 ! and LSEC of ICMSEC, AMSS(2001-2003)
 ! The copyright of the DFT system was declared by Walls at LASG, 1998-2010
 ! ======================================================================================
-#if (RWORDSIZE == 4)
+#ifndef DOUBLE_PRECISION
 #   define VPOWX vspowx
 #   define VPOW  vspow
 #else