diff --git a/src/crater/module_crater.f90 b/src/crater/module_crater.f90
index 1ab689b8..a5433e04 100644
--- a/src/crater/module_crater.f90
+++ b/src/crater/module_crater.f90
@@ -120,14 +120,14 @@ end subroutine crater_form_interior
    end interface
 
    interface
-      subroutine crater_form_exterior(user,surfi,crater,domain,lradsq,newelev,deltaMi)
+      subroutine crater_form_exterior(user,surfi,crater,domain,lradsq,newelev,rimheight,deltaMi)
       use module_globals
       implicit none
       type(usertype),intent(in) :: user
       type(surftype),intent(inout) :: surfi
       type(cratertype),intent(in) :: crater
       type(domaintype),intent(in) :: domain
-      real(DP),intent(in) :: newelev,lradsq
+      real(DP),intent(in) :: newelev,lradsq,rimheight
       real(DP),intent(out) :: deltaMi
       end subroutine crater_form_exterior
    end interface