One way to do this is to edit phys/module_physics_init.F in the subroutine landuse_init. Try adding a line in this part of the code, just before the last line quoted here:
!Set arrays according to lu_index
itf = min0(ite,ide-1)
jtf = min0(jte,jde-1)
IF(usemonalb)CALL wrf_message('Climatological albedo is used instead of table values')
DO j = jts,jtf
DO i = its,itf
IS=nint(lu_index(i,j))
so that the new section reads:
!Set arrays according to lu_index
itf = min0(ite,ide-1)
jtf = min0(jte,jde-1)
IF(usemonalb)CALL wrf_message('Climatological albedo is used instead of table values')
DO j = jts,jtf
DO i = its,itf
lu_index = 16
IS=nint(lu_index(i,j))
Recompile the code after making this change (no need to do a 'clean -a' or to reconfigure since you are not changing anything in the Registry file). Check the field LU_INDEX in the wrfout file.
!Set arrays according to lu_index
itf = min0(ite,ide-1)
jtf = min0(jte,jde-1)
IF(usemonalb)CALL wrf_message('Climatological albedo is used instead of table values')
DO j = jts,jtf
DO i = its,itf
IS=nint(lu_index(i,j))
so that the new section reads:
!Set arrays according to lu_index
itf = min0(ite,ide-1)
jtf = min0(jte,jde-1)
IF(usemonalb)CALL wrf_message('Climatological albedo is used instead of table values')
DO j = jts,jtf
DO i = its,itf
lu_index = 16
IS=nint(lu_index(i,j))
Recompile the code after making this change (no need to do a 'clean -a' or to reconfigure since you are not changing anything in the Registry file). Check the field LU_INDEX in the wrfout file.