diff --git a/esm-collections/cloud-access/dkrz_era5_disk.json b/esm-collections/cloud-access/dkrz_era5_disk.json
index cb44f2fd3f5226fac22e558035da85a1109906f8..4e12bd3b0aadf324046446c61068cb29cff63d34 100755
--- a/esm-collections/cloud-access/dkrz_era5_disk.json
+++ b/esm-collections/cloud-access/dkrz_era5_disk.json
@@ -93,11 +93,26 @@
     "aggregation_control": {
         "aggregations": [
             {
-                "attribute_name": "code",
-                "type": "union"
-            }
-        ],
-        "variable_column_name": "code",
+              "attribute_name": "validation_date",
+                "options": {
+                    "compat": "override",
+                    "coords": "minimal",
+                    "dim": "time"
+                },
+              "type": "join_existing"
+          },
+            {
+              "attribute_name": "initialization_date",
+                "options": {
+                    "compat": "override",
+                    "coords": "minimal",
+                    "dim": "time"
+                },
+              "type": "join_existing"
+          },
+          {"attribute_name": "short_name",
+           "type": "union"}],
+        "variable_column_name": "short_name",
         "groupby_attrs": [
             "table_id",
             "stepType",
diff --git a/esm-collections/disk-access/dkrz_era5_disk.json b/esm-collections/disk-access/dkrz_era5_disk.json
index ee926c1975ba0ab7f4876d0335d3287baa6083b1..c061248883d753a96404be7ee82817dc0045e6cf 100755
--- a/esm-collections/disk-access/dkrz_era5_disk.json
+++ b/esm-collections/disk-access/dkrz_era5_disk.json
@@ -77,9 +77,28 @@
       {"column_name": "format"}],
     "assets": {"format_column_name": "format", "column_name": "uri"},
     "aggregation_control": {
-      "aggregations": [{"attribute_name": "code",
-                        "type": "union"}],
-    "variable_column_name": "code",
+      "aggregations": [
+          {
+              "attribute_name": "validation_date",
+                "options": {
+                    "compat": "override",
+                    "coords": "minimal",
+                    "dim": "time"
+                },
+              "type": "join_existing"
+          },
+          {
+              "attribute_name": "initialization_date",
+                "options": {
+                    "compat": "override",
+                    "coords": "minimal",
+                    "dim": "time"
+                },
+              "type": "join_existing"
+          },
+          {"attribute_name": "short_name",
+           "type": "union"}],
+    "variable_column_name": "short_name",
     "groupby_attrs": [
       "table_id",
       "stepType",