diff --git a/src/gen_topo.f90 b/src/gen_topo.f90
index 7a6637f..9ca1e27 100644
--- a/src/gen_topo.f90
+++ b/src/gen_topo.f90
@@ -215,14 +215,12 @@ subroutine gen_topo(topo_file, out_file, grid_file, istripolar, offset)
     call handle_error(nf90_def_var(ncid_topo, 'depth_med', nf90_float, dids_topo, depth_med_id))
     call handle_error(nf90_def_var(ncid_topo, 'depth_all_med', nf90_float, dids_topo, depth_all_med_id))
     call handle_error(nf90_def_var(ncid_topo, 'sea_area_fraction', nf90_float, dids_topo, frac_id))
-    call handle_error(nf90_def_var(ncid_topo, 'geolon_t', nf90_float, dids, geolon_id, chunksizes=[nxt/10, nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid_topo, 'geolon_t', nf90_float, dids, geolon_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_put_att(ncid_topo, geolon_id, 'long_name', 'tracer longitude'))
     call handle_error(nf90_put_att(ncid_topo, geolon_id, 'units', 'degrees_E'))
     call handle_error(nf90_put_var(ncid_topo, geolon_id, x_t))
 
-    call handle_error(nf90_def_var(ncid_topo, 'geolat_t', nf90_float, dids, geolat_id, chunksizes=[nxt/10, nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid_topo, 'geolat_t', nf90_float, dids, geolat_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_put_att(ncid_topo, geolat_id, 'long_name', 'tracer latitude'))
     call handle_error(nf90_put_att(ncid_topo, geolat_id, 'units', 'degrees_N'))
     call handle_error(nf90_put_var(ncid_topo, geolat_id, y_t))
diff --git a/src/topography.f90 b/src/topography.f90
index 6e082ab..43923e9 100644
--- a/src/topography.f90
+++ b/src/topography.f90
@@ -163,8 +163,7 @@ subroutine topography_write(this, filename)
     call handle_error(nf90_def_dim(ncid, 'ny', this%nyt, dids(2)))
 
     ! Write depth
-    call handle_error(nf90_def_var(ncid, 'depth', nf90_float, dids, depth_id, chunksizes=[this%nxt/10, this%nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid, 'depth', nf90_float, dids, depth_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_def_var_fill(ncid, depth_id, 0, MISSING_VALUE))
     call handle_error(nf90_put_att(ncid, depth_id, 'long_name', 'depth'))
     call handle_error(nf90_put_att(ncid, depth_id, 'units', 'm'))
@@ -181,8 +180,7 @@ subroutine topography_write(this, filename)
     call handle_error(nf90_put_var(ncid, depth_id, this%depth))
 
     ! Write frac
-    call handle_error(nf90_def_var(ncid, 'sea_area_fraction', nf90_float, dids, frac_id, chunksizes=[this%nxt/10, this%nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid, 'sea_area_fraction', nf90_float, dids, frac_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_def_var_fill(ncid, frac_id, 0, MISSING_VALUE))
     call handle_error(nf90_put_var(ncid, frac_id, this%frac))
 
@@ -207,14 +205,12 @@ subroutine topography_write_coordinates(this, ncid, dids)
     integer(int32) :: geolon_id, geolat_id ! NetCDF ids
 
     ! Write coordinates
-    call handle_error(nf90_def_var(ncid, 'geolon_t', nf90_float, dids, geolon_id, chunksizes=[this%nxt/10, this%nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid, 'geolon_t', nf90_float, dids, geolon_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_put_att(ncid, geolon_id, 'long_name', 'tracer longitude'))
     call handle_error(nf90_put_att(ncid, geolon_id, 'units', 'degrees_E'))
     call handle_error(nf90_put_var(ncid, geolon_id, this%geolon_t))
 
-    call handle_error(nf90_def_var(ncid, 'geolat_t', nf90_float, dids, geolat_id, chunksizes=[this%nxt/10, this%nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid, 'geolat_t', nf90_float, dids, geolat_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_put_att(ncid, geolat_id, 'long_name', 'tracer latitude'))
     call handle_error(nf90_put_att(ncid, geolat_id, 'units', 'degrees_N'))
     call handle_error(nf90_put_var(ncid, geolat_id, this%geolat_t))
@@ -460,8 +456,7 @@ subroutine topography_deseas(this)
     call handle_error(nf90_create(trim('sea_num.nc'), ior(nf90_netcdf4, nf90_clobber), ncid))
     call handle_error(nf90_def_dim(ncid, 'nx', this%nxt, dids(1)))
     call handle_error(nf90_def_dim(ncid, 'ny', this%nyt, dids(2)))
-    call handle_error(nf90_def_var(ncid, 'sea_num', nf90_short, dids, sea_id, chunksizes=[this%nxt/10, this%nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid, 'sea_num', nf90_short, dids, sea_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_enddef(ncid))
     call handle_error(nf90_put_var(ncid, sea_id, sea))
     call handle_error(nf90_close(ncid))
@@ -747,8 +742,7 @@ subroutine topography_mask(this, filename)
     call this%write_coordinates(ncid, dids)
 
     ! Write mask
-    call handle_error(nf90_def_var(ncid, 'mask', nf90_float, dids, mask_id, chunksizes=[this%nxt/10, this%nyt/10], &
-      deflate_level=1, shuffle=.true.))
+    call handle_error(nf90_def_var(ncid, 'mask', nf90_float, dids, mask_id, deflate_level=1, shuffle=.true.))
     call handle_error(nf90_put_var(ncid, mask_id, mask))
 
     call handle_error(nf90_put_att(ncid, nf90_global, 'history', date_time()//": "//get_mycommand()))