diff --git a/modules/contrail/util.py b/modules/contrail/util.py
index 77cb685d85cab55ec74dcd994a81441f141115c6..1474f1ca9044045b7653355e00a9ef0e4714e985 100644
--- a/modules/contrail/util.py
+++ b/modules/contrail/util.py
@@ -110,7 +110,7 @@ def extract(mask_image, image_ts, clavrx_path):
     horz_wind_spd_3d = wind_speed(uwind_3d, vwind_3d)
 
     # This one's a bit more work: `first_derivative` only returns a ndarray with no units, so we use the
-    # helper function to create a DataArray and units via metpy's pint support
+    # helper function to create a DataArray and add units via metpy's pint support
     vert_shear_3d = first_derivative(horz_wind_spd_3d, axis=0, x=temp_3d.coords['Pressure'])
     vert_shear_3d = volume_np_to_xr(vert_shear_3d, ['Pressure', 'Latitude', 'Longitude'], lon_range=[lon_range[0], lon_range[1]], lat_range=[lat_range[0], lat_range[1]])
     vert_shear_3d = vert_shear_3d / units.hPa