diff --git a/src/gz21_ocean_momentum/step/data/lib.py b/src/gz21_ocean_momentum/step/data/lib.py
index f8f1a342..97e191fc 100644
--- a/src/gz21_ocean_momentum/step/data/lib.py
+++ b/src/gz21_ocean_momentum/step/data/lib.py
@@ -179,16 +179,14 @@ def _advections(u_v_field: xr.Dataset, grid_data: xr.Dataset):
         "xu_ocean": u_v_field.coords["xu_ocean"],
         "yu_ocean": u_v_field.coords["yu_ocean"],
     }
-    # TODO got "ValueError: zero-size array to reduction operation fmin which has
-    # no identity" when given 0 bounding box
     gradient_x = gradient_x.interp(interp_coords)
     gradient_y = gradient_y.interp(interp_coords)
     u, v = u_v_field["usurf"], u_v_field["vsurf"]
     adv_x = u * gradient_x["usurf"] + v * gradient_y["usurf"]
     adv_y = u * gradient_x["vsurf"] + v * gradient_y["vsurf"]
     result = xr.Dataset({"adv_x": adv_x, "adv_y": adv_y})
-    # TODO check if we can simply prevent the previous operation from adding
-    # chunks
+    # TODO 2023-09-20: old note from original import: v
+    # check if we can simply prevent the previous operation from adding chunks
     # result = result.chunk(dict(xu_ocean=-1, yu_ocean=-1))
     return result