diff --git a/parm/use_cases/model_applications/s2s/UserScript_obsERA_obsOnly_Stratosphere.conf b/parm/use_cases/model_applications/s2s/UserScript_obsERA_obsOnly_Stratosphere.conf
index 261df53b63..beff028e83 100644
--- a/parm/use_cases/model_applications/s2s/UserScript_obsERA_obsOnly_Stratosphere.conf
+++ b/parm/use_cases/model_applications/s2s/UserScript_obsERA_obsOnly_Stratosphere.conf
@@ -48,6 +48,8 @@ USER_SCRIPT_COMMAND = {PARM_BASE}/use_cases/model_applications/s2s/UserScript_ob
 
 # Difficulty index specific variables
 
+INPUT_FILE_NAME = {INPUT_BASE}/model_applications/s2s/UserScript_obsERA_obsOnly_Stratosphere
+
 LOG_FILE = "Meridonial_means.log"
 
 LOG_LEVEL = "INFO"