diff --git a/src/rook/utils/decadal_fixes.py b/src/rook/utils/decadal_fixes.py
index 686f325..a5a75b0 100644
--- a/src/rook/utils/decadal_fixes.py
+++ b/src/rook/utils/decadal_fixes.py
@@ -147,7 +147,7 @@ def decadal_fix_calendar(ds_id, ds, output_dir=None):
         ds.time.encoding["calendar"] = "standard"
         # need to write and read file to rewrite time dimension for the standard calendar!
         tmp_dir = tempfile.TemporaryDirectory(dir=output_dir)
-        fixed_nc = os.path.join(tmp_dir, "fixed_calendar.nc")
+        fixed_nc = os.path.join(tmp_dir.name, "fixed_calendar.nc")
         ds.to_netcdf(fixed_nc)
         ds = open_xr_dataset(fixed_nc)
         tmp_dir.cleanup()