diff --git a/run_bnn.py b/run_bnn.py
index 3642ec6d522aff51516a7eb710d00b04ab137d50..7667b027a4293a611a45355be635435e3fb0f3b1 100644
--- a/run_bnn.py
+++ b/run_bnn.py
@@ -49,6 +49,7 @@ def main(parser_args):
         statistics_per_var=stats_per_var,
         target_var="o3",
         target_var_unit="ppb",
+        num_realizations=30,
         **parser_args.__dict__, start_script=__file__)
     workflow.run()