Remove references to hemispheric afwa data.

Fixes ufs-community#973.

reg_tests/snow2mdl/snow2mdl.global.sh

@@ -8,8 +8,6 @@
 set -x
 
 export IMS_FILE=$HOMEreg/input_data/imssnow96.afwa.global.grb
-export AFWA_NH_FILE=""
-export AFWA_SH_FILE=""
 export AFWA_GLOBAL_FILE="$HOMEreg/input_data/afwa.global.grb2"
 
 export MODEL_LATITUDE_FILE=$HOMEgfs/fix/am/global_latitudes.t1534.3072.1536.grb

ush/emcsfc_snow.sh

@@ -22,8 +22,6 @@
 #    $MODEL_SLMASK_FILE    - model landmask  (grib 1 or 2)
 #    $MODEL_LATITUDE_FILE  - model latitude  (grib 1 or 2)
 #    $MODEL_LONGITUDE_FILE - model longitude (grib 1 or 2)
-#    $AFWA_NH_FILE         - nh afwa snow data (grib 1)
-#    $AFWA_SH_FILE         - sh afwa snow data (grib 1)
 #    $AFWA_GLOBAL_FILE     - global afwa snow data (grib 2)
 #    $IMS_FILE             - nh ims snow cover data (grib 2)
 #    $CLIMO_QC             - nh climatological snow cover (grib 2)
@@ -33,9 +31,8 @@
 #
 # Condition codes:
 #  0       - normal termination
-#  $rc1    - non-zero status indicates corrupt ims data.
-#  $rc2    - non-zero status indicates a problem in emcsfc_snow2mdl execution.
-#            see source code for details - /nwprod/gfs.vX.Y.Z/sorc/emcsfc_snow2mdl.fd
+#  non 0   - indicates missing or corrupt input data
+#            or a problem in emcsfc_snow2mdl execution.
 #
 # If a non-zero status occurs, no model snow analysis will be created.
 # This is not fatal to the model executation.  But any problems should
@@ -100,12 +97,9 @@ GFS_LONSPERLAT_FILE=${GFS_LONSPERLAT_FILE:-global_lonsperlat.t1534.3072.1536.txt
 
 #------------------------------------------------------------------------
 # Input snow data.  ims snow cover and afwa snow depth. ims is NH only.
-# In OPS, we run with ims only, or ims and afwa.  afwa data is too
-# unreliable to use on its own.  ims is grib2.  afwa is grib1.
+# AFWA is global.
 #------------------------------------------------------------------------
 
-AFWA_NH_FILE=${AFWA_NH_FILE:-"NPR.SNWN.SP.S1200.MESH16"}
-AFWA_SH_FILE=${AFWA_SH_FILE:-"NPR.SNWS.SP.S1200.MESH16"}
 AFWA_GLOBAL_FILE=${AFWA_GLOBAL_FILE:-""}
 IMS_FILE=${IMS_FILE:-"imssnow96.grb.grib2"}
 
@@ -182,8 +176,8 @@ cat > ./fort.41 << !
   nesdis_snow_file="${IMS_FILE}"
   nesdis_lsmask_file=""
   afwa_snow_global_file="${AFWA_GLOBAL_FILE}"
-  afwa_snow_nh_file="${AFWA_NH_FILE}"
-  afwa_snow_sh_file="${AFWA_SH_FILE}"
+  afwa_snow_nh_file=""
+  afwa_snow_sh_file=""
   afwa_lsmask_nh_file=""
   afwa_lsmask_sh_file=""
  /
@@ -216,7 +210,7 @@ cat > ./fort.41 << !
 eval $SNOW2MDLEXEC  >> $pgmout 2> errfile
 rc2=$?
 
-if ((rc2!= 0));then 
+if ((rc2 != 0));then 
   echo "WARNING: ${pgm} completed abnormally."
   exit $rc2
 else