diff --git a/srcF/sfx_def.fi b/srcF/sfx_def.fi
new file mode 100644
index 0000000000000000000000000000000000000000..6d90e998dd5de70047b481d47c4865f34ae97e81
--- /dev/null
+++ b/srcF/sfx_def.fi
@@ -0,0 +1,4 @@
+! sfx model macro definitions
+
+!#define SFX_FORCE_DEPRECATED_CODE
+!#define SFX_CHECK_NAN
\ No newline at end of file
diff --git a/srcF/sfx_esm.f90 b/srcF/sfx_esm.f90
index 2633a8481953c3891745f781e034b615491631a8..9dbe10ce7641670ee4ef27757b7e46e0ea856561 100644
--- a/srcF/sfx_esm.f90
+++ b/srcF/sfx_esm.f90
@@ -1,12 +1,8 @@
+#include "sfx_def.fi"
+
 module sfx_esm
     !> @brief main Earth System Model surface flux module
 
-    ! macro defs.
-    ! --------------------------------------------------------------------------------
-!#define SFX_FORCE_DEPRECATED_CODE
-!#define SFX_CHECK_NAN
-    ! --------------------------------------------------------------------------------
-
     ! modules used
     ! --------------------------------------------------------------------------------
 #ifdef SFX_CHECK_NAN
diff --git a/srcF/sfx_log.f90 b/srcF/sfx_log.f90
index a3c34655dd813972c3d95d1b4bc92f7697c49a86..17815449f8ec59452e57b837b0a7727d4c4a8525 100644
--- a/srcF/sfx_log.f90
+++ b/srcF/sfx_log.f90
@@ -1,10 +1,8 @@
+#include "sfx_def.fi"
+
 module sfx_log
     !> @brief simple log-roughness surface flux module
 
-    ! macro defs.
-    ! --------------------------------------------------------------------------------
-    ! --------------------------------------------------------------------------------
-
     ! modules used
     ! --------------------------------------------------------------------------------
 #ifdef SFX_CHECK_NAN
diff --git a/srcF/sfx_roughness.f90 b/srcF/sfx_roughness.f90
index 8e01cc9438299d1371783caa4ba81b51c12de45d..e5e5463ab8b16ab8c1f3daa0007099a690907562 100644
--- a/srcF/sfx_roughness.f90
+++ b/srcF/sfx_roughness.f90
@@ -1,10 +1,8 @@
+#include "sfx_def.fi"
+
 module sfx_roughness
     !> @brief surface roughness parameterizations
 
-    ! macro defs.
-    ! --------------------------------------------------------------------------------
-    ! --------------------------------------------------------------------------------
-
     ! modules used
     ! --------------------------------------------------------------------------------
     use sfx_phys_const