diff --git a/modules/util/viirs.py b/modules/util/viirs.py
index 6d500b35404e280c222ce24afeecd89da9f79fe0..ce6d533e26bbf41a013047ae5b9d0135ef829505 100644
--- a/modules/util/viirs.py
+++ b/modules/util/viirs.py
@@ -112,7 +112,9 @@ def run_mean_std(directory):
             if idx % 8 == 0:
                 h5f = h5py.File(mfile, 'r')
                 for param in mod_res_params:
-                    gvals = get_grid_values_all(h5f, 'observation_data/'+param, range_name=None, stride=10)
+                    name = 'observation_data/'+param
+                    print(name)
+                    gvals = get_grid_values_all(h5f, name, range_name=None, stride=10)
                     data_dct[param].append(gvals.flatten())
                 print(mfile)
                 h5f.close()