diff --git a/definitions/grib1/local.98.12.def b/definitions/grib1/local.98.12.def
index 3a65f98b6..d0b76d61d 100644
--- a/definitions/grib1/local.98.12.def
+++ b/definitions/grib1/local.98.12.def
@@ -57,8 +57,12 @@ alias totalNumber=numberOfForecastsInEnsemble;
 
 unsigned[4] indexingDate: dump; # MARS archiving date (YYYYMMDD)
 unsigned[2] indexingTime: dump; # MARS archiving time (HHMM)
+transient indexingTimeHH = indexingTime/100 : hidden;
+transient indexingTimeMM = indexingTime - 100 * indexingTimeHH : hidden;
+meta indexingTimeHHMM sprintf("%.2d%.2d",indexingTimeHH,indexingTimeMM);
+
 alias mars.date = indexingDate;
-alias mars.time = indexingTime;
+alias mars.time = indexingTimeHHMM;
 
 # spareSetToZero
 pad padding_loc12_1(50);
diff --git a/definitions/grib2/local.98.12.def b/definitions/grib2/local.98.12.def
index 8632fd6a6..355362b5e 100644
--- a/definitions/grib2/local.98.12.def
+++ b/definitions/grib2/local.98.12.def
@@ -8,7 +8,11 @@ alias local.methodNumber=methodNumber;
 
 unsigned[4] indexingDate: dump; # MARS archiving date (YYYYMMDD)
 unsigned[2] indexingTime: dump; # MARS archiving time (HHMM)
+transient indexingTimeHH = indexingTime/100 : hidden;
+transient indexingTimeMM = indexingTime - 100 * indexingTimeHH : hidden;
+meta indexingTimeHHMM sprintf("%.2d%.2d",indexingTimeHH,indexingTimeMM);
+
 alias mars.date = indexingDate;
-alias mars.time = indexingTime;
+alias mars.time = indexingTimeHHMM;
 
 pad padding_loc12_1(50);