diff --git a/definitions/create_legacy_def.sh b/definitions/create_legacy_def.sh
new file mode 100755
index 000000000..0218f4eff
--- /dev/null
+++ b/definitions/create_legacy_def.sh
@@ -0,0 +1,50 @@
+:
+set -eu
+
+pid=$1
+
+sample2=samples/GRIB2.tmpl
+temp=$TMPDIR/temp.create_legacy_def.grib
+defs=definitions/grib2/localConcepts/ecmf
+
+output_def()
+{
+    _name=$1
+    _val=$2
+    _d=$3
+    _c=$4
+    _n=$5
+
+    if [ $_c -eq 0 ]; then
+        _c=128
+    fi
+    if [ "$_val" != "unknown" ]; then
+        echo "#$_name"
+        echo "'$_val' = {"
+        echo " discipline = $_d ;"
+        echo " parameterCategory = $_c ;"
+        echo " parameterNumber = $_n ;"
+        echo "}"
+    fi
+}
+
+grib_set -s paramId=$pid $sample2 $temp
+name=$(grib_get -p name $temp)
+shortName=$(grib_get -p shortName $temp)
+units=$(grib_get -p units $temp)
+cfName=$(grib_get -p cfName $temp)
+cfVarName=$(grib_get -p cfVarName $temp)
+
+dis=192
+cat=$((pid/1000))
+num=$((pid - cat*1000))
+
+output_def "$name" "$pid"       $dis $cat $num >> $defs/paramId.legacy.def
+output_def "$name" "$name"      $dis $cat $num >> $defs/name.legacy.def
+output_def "$name" "$shortName" $dis $cat $num >> $defs/shortName.legacy.def
+output_def "$name" "$units"     $dis $cat $num >> $defs/units.legacy.def
+output_def "$name" "$cfVarName" $dis $cat $num >> $defs/cfVarName.legacy.def
+output_def "$name" "$cfName"    $dis $cat $num >> $defs/cfName.legacy.def
+
+echo "Files updated"
+rm -f $temp