change conus3km GSIBEC parameters to those generated by MPAS grid with a grid_ratio=2.0

Author: Junjun-NOAA

workflow/exp/exp.conus3km

@@ -29,14 +29,14 @@ export ENS_BEC_LOOK_BACK_HRS=1  # define the hours going back for ensemble forec
 export STATIC_BEC_MODEL="GSIBEC" # the static bec model, GSIBEC and BUMPBEC
 export GSIBEC_X=40 #GSIBEC_X * GSIBEC_Y should match the number of MPI tasks
 export GSIBEC_Y=20
-export GSIBEC_NLAT=1092
-export GSIBEC_NLON=1820
-export GSIBEC_NORTH_POLE_LAT=128.500000
-export GSIBEC_NORTH_POLE_LON=82.500002
-export GSIBEC_LON_START=-50.159868
-export GSIBEC_LON_END=50.159868
-export GSIBEC_LAT_START=-29.433115
-export GSIBEC_LAT_END=29.433115
+export GSIBEC_NLAT=593
+export GSIBEC_NLON=921
+export GSIBEC_NORTH_POLE_LAT=51.226749
+export GSIBEC_NORTH_POLE_LON=82.592899
+export GSIBEC_LON_START=-24.840000
+export GSIBEC_LON_END=24.840000
+export GSIBEC_LAT_START=-15.984000
+export GSIBEC_LAT_END=15.984000
 
 export DO_CYC=true
 export CYC_INTERVAL=1