diff --git a/physics/MP/Thompson/module_mp_thompson_make_number_concentrations.F90 b/physics/MP/Thompson/module_mp_thompson_make_number_concentrations.F90
index a54f910c9..7618b0a9f 100644
--- a/physics/MP/Thompson/module_mp_thompson_make_number_concentrations.F90
+++ b/physics/MP/Thompson/module_mp_thompson_make_number_concentrations.F90
@@ -137,13 +137,15 @@ elemental real function make_DropletNumber (Q_cloud, qnwfa)
       real, intent(in):: Q_cloud, qnwfa
 
       !real, parameter:: PI = 3.1415926536
-      real, parameter:: am_r = PI*1000./6.
+      real :: am_r
       real, dimension(15), parameter:: g_ratio = (/24,60,120,210,336,   &
      &                504,720,990,1320,1716,2184,2730,3360,4080,4896/)
       double precision:: lambda, qnc
       real:: q_nwfa, x1, xDc
       integer:: nu_c
 
+      am_r = PI*1000./6.
+
       if (Q_cloud == 0) then
          make_DropletNumber = 0
          return
@@ -176,7 +178,9 @@ elemental real function make_RainNumber (Q_rain, temp)
       real, intent(in):: Q_rain, temp
       double precision:: lambda, N0, qnr
       !real, parameter:: PI = 3.1415926536
-      real, parameter:: am_r = PI*1000./6.
+      real :: am_r
+
+      am_r = PI*1000./6.
 
       if (Q_rain == 0) then
          make_RainNumber = 0