diff --git a/regression/global_enkf.sh b/regression/global_enkf.sh
index a35f8d109..f5b4f3d1c 100755
--- a/regression/global_enkf.sh
+++ b/regression/global_enkf.sh
@@ -76,14 +76,11 @@ export use_correlated_oberrs=${use_correlated_oberrs:-".false."}
 if [ $USE_CORRELATED_OBERRS == "YES" ]; then
     export use_correlated_oberrs=".true."
 fi
-export imp_physics=${imp_physics:-"11"}
 export lupp=${lupp:-".true."}
 export corrlength=${corrlength:-1250}
 export lnsigcutoff=${lnsigcutoff:-2.75}
 export analpertwt=${analpertwt:-0.85}
 export readin_localization_enkf=".false."
-export readin_localization_enkf=${readin_localization_enkf:-".true."}
-export reducedgrid=${reducedgrid:-".true."}
 export letkf_flag=${letkf_flag:-".true."}
 export getkf=${getkf:-".true."}
 export denkf=${denkf:-".true."}
diff --git a/regression/regression_namelists.sh b/regression/regression_namelists.sh
index a4f283f92..a6bd78994 100755
--- a/regression/regression_namelists.sh
+++ b/regression/regression_namelists.sh
@@ -23,12 +23,12 @@ export gsi_namelist="
    crtm_coeffs_path='./crtm_coeffs/',
    newpc4pred=.true.,adp_anglebc=.true.,angord=4,passive_bc=.true.,use_edges=.false.,
    diag_precon=.true.,step_start=1.e-3,emiss_bc=.true.,thin4d=.true.,cwoption=3,
-   verbose=.false.,imp_physics=11,lupp=.true.,
+   verbose=.false.,imp_physics=8,lupp=.true.,
    binary_diag=.false.,netcdf_diag=.true.,
    lobsdiag_forenkf=.false.,
    nhr_anal=3,6,9,nhr_obsbin=1,
    l4densvar=.true.,ens_nstarthr=3,nhr_assimilation=6,lwrite4danl=.true.,
-   optconv=0.05,cao_check=.true.,ta2tb=.false.,
+   optconv=0.05,cao_check=.true.,ta2tb=.true.,
    tzr_qc=1,sfcnst_comb=.true.,
    write_fv3_incr=.true.,incvars_to_zero= 'liq_wat_inc','icmr_inc','rwmr_inc','snmr_inc','grle_inc',
    incvars_zero_strat='sphum_inc','liq_wat_inc','icmr_inc','rwmr_inc','snmr_inc','grle_inc',incvars_efold=5, use_gfs_ncio=.true.,
@@ -962,8 +962,8 @@ export gsi_namelist="
   sprd_tol=1.e30,paoverpb_thresh=0.98,
   nlons=$LONA,nlats=$LATA,nlevs=$LEVS,nanals=$NMEM_ENKF,
   deterministic=.true.,sortinc=.true.,lupd_satbiasc=.false.,
-  reducedgrid=.true.,readin_localization=.true.,
-  use_gfs_nemsio=${use_gfs_nemsio},use_gfs_ncio=${use_gfs_ncio},imp_physics=$imp_physics,lupp=$lupp,
+  reducedgrid=.false.,readin_localization=.false.,
+  use_gfs_nemsio=${use_gfs_nemsio},use_gfs_ncio=${use_gfs_ncio},imp_physics=8,lupp=$lupp,
   univaroz=.false.,adp_anglebc=.true.,angord=4,use_edges=.false.,emiss_bc=.true.,
   letkf_flag=${letkf_flag},nobsl_max=${nobsl_max},denkf=${denkf},getkf=${getkf}.,
   nhr_anal=${IAUFHRS_ENKF},nhr_state=${IAUFHRS_ENKF},
diff --git a/regression/regression_namelists_db.sh b/regression/regression_namelists_db.sh
index b96c20807..34d80cba9 100755
--- a/regression/regression_namelists_db.sh
+++ b/regression/regression_namelists_db.sh
@@ -21,7 +21,7 @@ export gsi_namelist="
    crtm_coeffs_path='./crtm_coeffs/',
    newpc4pred=.true.,adp_anglebc=.true.,angord=4,passive_bc=.true.,use_edges=.false.,
    diag_precon=.true.,step_start=1.e-3,emiss_bc=.true.,thin4d=.true.,cwoption=3,
-   verbose=.false.,imp_physics=11,lupp=.true.,binary_diag=.false.,netcdf_diag=.true.,
+   verbose=.false.,imp_physics=8,lupp=.true.,binary_diag=.false.,netcdf_diag=.true.,
    lobsdiag_forenkf=.false.,
    nhr_anal=3,6,9,
    l4densvar=.true.,ens_nstarthr=3,nhr_obsbin=1,nhr_assimilation=6,lwrite4danl=.true., tzr_qc=1,sfcnst_comb=.true.,