diff --git a/physics/aerclm_def.F b/physics/aerclm_def.F
index 157c7b961..e66825278 100644
--- a/physics/aerclm_def.F
+++ b/physics/aerclm_def.F
@@ -1,5 +1,5 @@
       module aerclm_def
-      use machine , only : kind_phys
+      use machine , only : kind_phys, kind_io4
       implicit none
 
       integer, parameter   :: levsaer=72, ntrcaerm=15, timeaer=12
@@ -10,13 +10,13 @@ module aerclm_def
 
       real (kind=kind_phys), allocatable, dimension(:) :: aer_lat
       real (kind=kind_phys), allocatable, dimension(:) :: aer_lon
-      real (kind=kind_phys), allocatable, dimension(:,:,:,:) :: aer_pres
-      real (kind=kind_phys), allocatable, dimension(:,:,:,:,:) :: aerin
+      real (kind=kind_io4),  allocatable, dimension(:,:,:,:) :: aer_pres
+      real (kind=kind_io4),  allocatable, dimension(:,:,:,:,:) :: aerin
 
       data aer_time/15.5, 45.,  74.5,  105., 135.5, 166., 196.5,
      &             227.5, 258., 288.5, 319., 349.5, 380.5/
 
-      data specname /'DU001','DU002','DU003','DU004','DU005', 
+      data specname /'DU001','DU002','DU003','DU004','DU005',
      &               'SS001','SS002','SS003','SS004','SS005','SO4',
      &               'BCPHOBIC','BCPHILIC','OCPHOBIC','OCPHILIC'/
 
diff --git a/physics/aerinterp.F90 b/physics/aerinterp.F90
index dbcf73603..4b3232ab1 100644
--- a/physics/aerinterp.F90
+++ b/physics/aerinterp.F90
@@ -181,7 +181,7 @@ SUBROUTINE read_aerdataf (iamin, iamax, jamin, jamax,           &
              endif
              do i = iamin, iamax
                aerin(i,j,k,ii,imon) = 1.d0*buffx(i,j,klev,1)
-               if(aerin(i,j,k,ii,imon) < 0 .or. aerin(i,j,k,ii,imon) > 1.)  then
+               if(aerin(i,j,k,ii,imon) < 0. .or. aerin(i,j,k,ii,imon) > 1.)  then
                  aerin(i,j,k,ii,imon) = 1.e-15
                endif
              enddo   !i-loop (lon)